diff --git a/src/assets/data/interfaces.ts b/src/assets/data/interfaces.ts
index db95a23e..452d4b31 100644
--- a/src/assets/data/interfaces.ts
+++ b/src/assets/data/interfaces.ts
@@ -7,10 +7,17 @@ export interface StatMatcher {
   value?: number
 }
 
+export enum StatBetter {
+  NegativeRoll = -1,
+  PositiveRoll = 1,
+  NotComparable = 0
+}
+
 export interface Stat {
   ref: string
   dp?: true
   matchers: StatMatcher[]
+  better: StatBetter
   trade: {
     inverted?: true
     option?: 'num' | 'str'
diff --git a/src/parser/advanced-mod-desc.ts b/src/parser/advanced-mod-desc.ts
index f44cbaa9..0c1ea9f9 100644
--- a/src/parser/advanced-mod-desc.ts
+++ b/src/parser/advanced-mod-desc.ts
@@ -137,9 +137,9 @@ export function applyIncr (mod: ModifierInfo, parsed: ParsedStat): ParsedStat |
     roll: {
       unscalable: roll.unscalable,
       dp: roll.dp,
-      value: percentRoll(roll.value, rollIncr, (roll.value > 0) ? Math.floor : Math.ceil, roll.dp && DIV_BY_100),
-      min: percentRoll(roll.min, rollIncr, (roll.min > 0) ? Math.floor : Math.ceil, roll.dp && DIV_BY_100),
-      max: percentRoll(roll.max, rollIncr, (roll.max > 0) ? Math.floor : Math.ceil, roll.dp && DIV_BY_100)
+      value: percentRoll(roll.value, rollIncr, Math.trunc, roll.dp && DIV_BY_100),
+      min: percentRoll(roll.min, rollIncr, Math.trunc, roll.dp && DIV_BY_100),
+      max: percentRoll(roll.max, rollIncr, Math.trunc, roll.dp && DIV_BY_100)
     }
   }
 }
diff --git a/src/web/price-check/filters/FilterModifier.vue b/src/web/price-check/filters/FilterModifier.vue
index 552ed67b..48526685 100644
--- a/src/web/price-check/filters/FilterModifier.vue
+++ b/src/web/price-check/filters/FilterModifier.vue
@@ -1,8 +1,8 @@
 <template>
   <div :class="$style['filter']">
-    <div :class="$style['mods']">
-      <div class="pl-5 pr-3 py-1" v-for="(source, idx) of filter.sources" :key="idx">
-        <source-info :source="source" />
+    <div v-if="showSourceInfo" :class="$style['mods']">
+      <div class="pl-5 py-1" v-for="(source, idx) of filter.sources" :key="idx">
+        <source-info :source="source" :filter="filter" />
       </div>
     </div>
     <div class="flex flex-col min-w-0 flex-1">
@@ -195,7 +195,7 @@ export default defineComponent({
         set (value: string) { props.filter.roll!.max = Number(value) }
       }),
       tag: computed(() => props.filter.tag),
-      changeStep: computed(() => props.filter.roll!.step),
+      changeStep: computed(() => props.filter.roll!.dp ? 0.01 : 1),
       showInputs: computed(() => props.filter.roll != null),
       fontSize: computed(() => AppConfig().fontSize),
       isDisabled: computed(() => props.filter.disabled),
@@ -205,6 +205,15 @@ export default defineComponent({
       showRollBounds: computed(() => props.filter.roll?.bounds != null),
       isHidden: computed(() => props.filter.hidden != null),
       hiddenReason: computed(() => t(props.filter.hidden!)),
+      showSourceInfo: computed(() =>
+        props.filter.sources.length &&
+        props.filter.option == null && (
+          props.filter.sources.length >= 2 ||
+          props.filter.sources[0].modifier.info.name != null ||
+          props.filter.sources[0].modifier.info.tier != null ||
+          props.filter.sources[0].modifier.info.rank != null
+        )
+      ),
       inputFocus,
       toggleFilter
     }
diff --git a/src/web/price-check/filters/SourceInfo.vue b/src/web/price-check/filters/SourceInfo.vue
index 75ea6b14..0d04be26 100644
--- a/src/web/price-check/filters/SourceInfo.vue
+++ b/src/web/price-check/filters/SourceInfo.vue
@@ -3,7 +3,7 @@
     <div :class="$style['modinfo']">{{ modText }}</div>
     <div v-for="stat of stats" :key="stat.text" class="flex">
       <item-modifier-text :text="stat.text" :roll="stat.roll" :class="{ 'line-through': !stat.contributes }" />
-      <div v-if="stat.contributes && stat.contribution" class="ml-auto">{{ stat.contribution }}</div>
+      <div v-if="stat.contributes && stat.contribution" :class="$style['contribution']">{{ stat.contribution }}</div>
     </div>
   </div>
 </template>
@@ -11,10 +11,11 @@
 <script lang="ts">
 import { computed, defineComponent, PropType } from 'vue'
 import { useI18n } from 'vue-i18n'
-import type { StatCalculated } from '@/parser/modifiers'
 import { applyIncr } from '@/parser/advanced-mod-desc'
 import { roundRoll } from './util'
 import ItemModifierText from '@/web/ui/ItemModifierText.vue'
+import type { StatCalculated } from '@/parser/modifiers'
+import type { StatFilter } from './interfaces'
 
 export default defineComponent({
   components: { ItemModifierText },
@@ -22,6 +23,10 @@ export default defineComponent({
     source: {
       type: Object as PropType<StatCalculated['sources'][number]>,
       required: true
+    },
+    filter: {
+      type: Object as PropType<StatFilter>,
+      required: true
     }
   },
   setup (props) {
@@ -47,8 +52,12 @@ export default defineComponent({
       const { stats } = props.source.modifier
       const { stat: contribStat } = props.source.stat
 
-      // TODO: percentRoll, isNegated
-      const contribution = props.source.contributes?.value
+      let contribution = props.source.contributes?.value
+      if (contribution != null) {
+        const filter = props.filter.roll!
+        contribution *= (filter.isNegated) ? -1 : 1
+        contribution = roundRoll(contribution, filter.dp)
+      }
 
       return stats.map((parsed) => {
         if (parsed.stat.ref !== contribStat.ref) {
@@ -89,6 +98,14 @@ export default defineComponent({
   @apply text-gray-500;
   font-style: italic;
 }
+
+.contribution {
+  margin-left: auto;
+  @apply w-12;
+  @apply rounded;
+  @apply border border-gray-700;
+  text-align: center;
+}
 </style>
 
 <i18n>
diff --git a/src/web/price-check/filters/create-stat-filters.ts b/src/web/price-check/filters/create-stat-filters.ts
index 4db2f177..407cd31e 100644
--- a/src/web/price-check/filters/create-stat-filters.ts
+++ b/src/web/price-check/filters/create-stat-filters.ts
@@ -1,11 +1,12 @@
 import { ParsedItem, ItemRarity, ItemCategory } from '@/parser'
-import { ModifierType, StatCalculated, StatRoll, statSourcesTotal, translateStatWithRoll } from '@/parser/modifiers'
+import { ModifierType, StatCalculated, statSourcesTotal, translateStatWithRoll } from '@/parser/modifiers'
 import { uniqueModFilterPartial } from './unique-roll'
-import { rollToFilter, percentRoll, roundRoll } from './util'
+import { percentRoll, roundRoll } from './util'
 import { FilterTag, ItemHasEmptyModifier, StatFilter } from './interfaces'
 import { filterPseudo } from './pseudo'
 import { filterItemProp } from './pseudo/item-property'
 import { filterUniqueItemProp } from './pseudo/item-property-unique'
+import { StatBetter } from '@/assets/data'
 
 export interface FiltersCreationContext {
   readonly item: ParsedItem
@@ -133,7 +134,21 @@ export function calculatedStatToFilter (
     ) {
       uniqueModFilterPartial(item, roll, filter, (opts.percent * 2), dp)
     } else {
-      itemModFilterPartial(calc, roll, filter, opts.percent, dp)
+      const percent = (calc.type === ModifierType.Enchant)
+        ? 0
+        : opts.percent
+
+      filter.roll = {
+        value: roundRoll(roll.value, dp),
+        min: undefined,
+        max: undefined,
+        default: {
+          min: percentRoll(roll.value, -percent, Math.floor, dp),
+          max: percentRoll(roll.value, +percent, Math.ceil, dp)
+        },
+        dp: dp,
+        isNegated: false
+      }
     }
   }
 
@@ -142,31 +157,6 @@ export function calculatedStatToFilter (
   return filter
 }
 
-function itemModFilterPartial (
-  calc: StatCalculated,
-  roll: StatRoll,
-  filter: StatFilter,
-  percent: number,
-  dp: boolean
-) {
-  if (roll) {
-    if (calc.type === ModifierType.Enchant) {
-      filter.roll = {
-        value: roundRoll(roll.value, dp),
-        min: percentRoll(roll.value, 0, Math.floor, dp),
-        max: percentRoll(roll.value, 0, Math.ceil, dp),
-        default: {
-          min: percentRoll(roll.value, 0, Math.floor, dp),
-          max: percentRoll(roll.value, 0, Math.ceil, dp)
-        },
-        step: dp ? 0.01 : 1
-      }
-    } else {
-      filter.roll = rollToFilter(roll.value, { dp: dp, percent })
-    }
-  }
-}
-
 function filterAdjustmentForNegate (
   calc: StatCalculated,
   negate: boolean,
@@ -176,37 +166,41 @@ function filterAdjustmentForNegate (
 
   const { roll } = filter
 
+  if (roll.min == null && roll.max == null) {
+    switch (calc.stat.better) {
+      case StatBetter.PositiveRoll:
+        roll.min = roll.default.min
+        break
+      case StatBetter.NegativeRoll:
+        roll.max = roll.default.max
+        break
+      case StatBetter.NotComparable:
+        roll.min = roll.default.min
+        roll.max = roll.default.max
+        break
+    }
+  }
+
   if (negate) {
     roll.tradeInvert = true
+    roll.isNegated = true
     const swap = JSON.parse(JSON.stringify(roll)) as typeof roll
 
-    if (roll.bounds) {
-      roll.bounds.min = -1 * swap.bounds!.max
-      roll.bounds.max = -1 * swap.bounds!.min
+    if (swap.bounds) {
+      roll.bounds!.min = -1 * swap.bounds.max
+      roll.bounds!.max = -1 * swap.bounds.min
     }
 
     roll.default.min = -1 * swap.default.max
     roll.default.max = -1 * swap.default.min
 
-    if (roll.min == null && roll.max == null) {
-      // TODO: for some stats reduced is better
-      roll.min = -1 * swap.default.max
-    } else {
-      if (roll.max != null) {
-        roll.min = -1 * (swap.max as number)
-      }
-      if (roll.min != null) {
-        roll.max = -1 * (swap.min as number)
-      }
-    }
-    if (roll.value != null) {
-      roll.value = -1 * swap.value
-    }
-  } else {
-    if (roll.min == null && roll.max == null) {
-      // TODO: for some stats reduced is better
-      roll.min = roll.default.min
-    }
+    roll.value = -1 * swap.value
+    roll.min = (typeof swap.max === 'number')
+      ? -1 * swap.max
+      : undefined
+    roll.max = (typeof swap.min === 'number')
+      ? -1 * swap.min
+      : undefined
   }
 
   if (calc.stat.trade.inverted) {
diff --git a/src/web/price-check/filters/interfaces.ts b/src/web/price-check/filters/interfaces.ts
index ec054e1f..1593c563 100644
--- a/src/web/price-check/filters/interfaces.ts
+++ b/src/web/price-check/filters/interfaces.ts
@@ -91,7 +91,8 @@ export interface StatFilter {
     default: { min: number, max: number }
     bounds?: { min: number, max: number }
     tradeInvert?: boolean
-    step: number
+    dp: boolean | number
+    isNegated: boolean
   }
   option?: {
     value: number // NOTE: mutable in UI
diff --git a/src/web/price-check/filters/unique-roll.ts b/src/web/price-check/filters/unique-roll.ts
index 958669dd..d5f50a44 100644
--- a/src/web/price-check/filters/unique-roll.ts
+++ b/src/web/price-check/filters/unique-roll.ts
@@ -27,7 +27,8 @@ export function uniqueModFilterPartial (
         min: statRoll.value,
         max: statRoll.value
       },
-      step: dp ? 0.01 : 1
+      dp: dp,
+      isNegated: false
     }
 
     if (filter.tag !== FilterTag.Variant && filter.tag !== FilterTag.Corrupted) {
@@ -46,7 +47,8 @@ export function uniqueModFilterPartial (
         min: statRoll.min,
         max: statRoll.max
       },
-      step: dp ? 0.01 : 1
+      dp: dp,
+      isNegated: false
     }
   }
 }
diff --git a/src/web/price-check/filters/util.ts b/src/web/price-check/filters/util.ts
index 96dc4e0b..741eb2fc 100644
--- a/src/web/price-check/filters/util.ts
+++ b/src/web/price-check/filters/util.ts
@@ -10,14 +10,16 @@ function decimalPlaces (value: number, dp: number | boolean): number {
   }
 }
 
-export function roundRoll (value: number, dp: number | boolean) {
-  const round = Math.pow(10, decimalPlaces(value, dp))
-  // round value down (toward zero)
-  return Math.trunc(value * round) / round
-}
+export const roundRoll = (value: number, dp: number | boolean) =>
+  percentRoll(value, 0, Math.trunc, dp)
 
-export function percentRoll (value: number, p: number, method: Math['floor'] | Math['ceil'], dp: number | boolean = false): number {
-  const res = value + value * p / 100
+export function percentRoll (
+  value: number,
+  p: number,
+  method: Math['floor'] | Math['ceil'] | Math['trunc'],
+  dp: number | boolean = false
+): number {
+  const res = value + Math.abs(value) * p / 100
 
   const rounding = Math.pow(10, decimalPlaces(value, dp))
   return method((res + Number.EPSILON) * rounding) / rounding
@@ -32,21 +34,19 @@ export function percentRollDelta (value: number, delta: number, p: number, metho
 
 export function rollToFilter (
   roll: number,
-  opts: { percent: number, neverNegated?: true, dp?: boolean | number }
+  opts: { percent: number, neverNegated: true, dp?: boolean | number }
 ): StatFilter['roll'] {
-  const { percent, neverNegated, dp } = opts
+  const { percent, dp } = opts
 
-  // opts.neverNegated is false only in one case, but keep it
-  // disabled by default, so opts.neverNegated acts more like
-  // acknowledgment of what you are doing
   return {
     value: roundRoll(roll, dp ?? false),
-    default: {
-      min: percentRoll(roll, -percent * Math.sign(roll), Math.floor, dp),
-      max: percentRoll(roll, +percent * Math.sign(roll), Math.ceil, dp)
-    },
-    min: neverNegated ? percentRoll(roll, -percent * Math.sign(roll), Math.floor, dp) : undefined,
+    min: percentRoll(roll, -percent, Math.floor, dp),
     max: undefined,
-    step: dp ? 0.01 : 1
+    default: {
+      min: percentRoll(roll, -percent, Math.floor, dp),
+      max: percentRoll(roll, +percent, Math.ceil, dp)
+    },
+    dp: dp ?? false,
+    isNegated: false
   }
 }