diff --git a/resources/tester/test_est_change_workflow.py b/resources/tester/test_est_change_workflow.py
index 44b9170c6..55258169d 100644
--- a/resources/tester/test_est_change_workflow.py
+++ b/resources/tester/test_est_change_workflow.py
@@ -1,6 +1,42 @@
 from test_est_rea_parity import run
 
 
+def test_design_change_costs_include_duplicate_new_and_deleted_cost_rows():
+    result = run(
+        "math",
+        """(()=>{
+      const p=EstNative.empty();p.tables.Wonga=[
+        {Gubun:'A',Name:'first',Cost:200},{Gubun:'A',Name:'second',Cost:60},
+        {Gubun:'C',Name:'new',Cost:25}];
+      p.baseline={name:'old',tables:{EstMainDat:[],Wonga:[
+        {Gubun:'A',Name:'first',Cost:100},{Gubun:'A',Name:'second',Cost:50},
+        {Gubun:'B',Name:'removed',Cost:30}]}};
+      const before=JSON.stringify(p), rows=EstBusiness.costChanges(p);
+      const output=EstForms.data('change-costs',p);
+      const node={innerHTML:''};globalThis.EstApp={esc:x=>String(x??''),number:x=>String(x??0),byId:()=>node};
+      EstExtra.render({project:p,view:'change'});
+      return {rows,output,html:node.innerHTML,same:before===JSON.stringify(p)};
+    })()""",
+    )
+    assert result["same"]
+    assert [row["difference"] for row in result["rows"]] == [100, 10, 25, -30]
+    assert result["output"]["rows"] == result["rows"]
+    assert "removed" in result["html"]
+
+
+def test_stored_original_costs_remain_attached_to_each_duplicate_row():
+    result = run(
+        "math",
+        """(()=>{
+      const p=EstNative.empty();p.tables.Wonga=[
+        {Gubun:'A',Name:'new',Cost:10},{Gubun:'A',Name:'existing',Cost:50,Cost_:30}];
+      return EstBusiness.costChanges(p);
+    })()""",
+    )
+    assert [row["originalCost"] for row in result] == [0, 30]
+    assert [row["difference"] for row in result] == [10, 20]
+
+
 def test_change_view_includes_named_rows_without_codes():
     result = run(
         "math",
diff --git a/tools/est-test/native-business.js b/tools/est-test/native-business.js
index 2731f2c78..e64fd54b2 100644
--- a/tools/est-test/native-business.js
+++ b/tools/est-test/native-business.js
@@ -105,6 +105,50 @@ const EstBusiness = (() => {
     });
     return changes;
   }
+  function costChanges(project) {
+    const current = project.tables.Wonga || [];
+    if (!project.baseline) {
+      if (!current.some((row) => row.Cost_ != null)) return [];
+      return current.map((row) => ({
+        Gubun: row.Gubun,
+        Name: row.Name,
+        originalCost: num(row.Cost_),
+        changedCost: num(row.Cost),
+        difference: num(row.Cost) - num(row.Cost_),
+      }));
+    }
+    const old = project.baseline.tables.Wonga || [];
+    function keyed(rows) {
+      const counts = new Map();
+      return rows.map((row) => {
+        const identity = JSON.stringify(row.Gubun ? ["code", row.Gubun] : ["name", row.Name || ""]);
+        const occurrence = counts.get(identity) || 0;
+        counts.set(identity, occurrence + 1);
+        return { row, key: JSON.stringify([identity, occurrence]) };
+      });
+    }
+    const previous = new Map(keyed(old).map(({ row, key }) => [key, row]));
+    const rows = keyed(current).map(({ row, key }) => {
+      const saved = previous.get(key);
+      previous.delete(key);
+      return {
+        Gubun: row.Gubun,
+        Name: row.Name,
+        originalCost: num(saved?.Cost),
+        changedCost: num(row.Cost),
+        difference: num(row.Cost) - num(saved?.Cost),
+      };
+    });
+    for (const row of previous.values())
+      rows.push({
+        Gubun: row.Gubun,
+        Name: row.Name,
+        originalCost: num(row.Cost),
+        changedCost: 0,
+        difference: -num(row.Cost),
+      });
+    return rows;
+  }
   function bid(project, rates) {
     const next = copy(project);
     for (const key of ["HeadMainDat", "EstMainDat"])
@@ -298,6 +342,7 @@ const EstBusiness = (() => {
   return {
     baseline,
     changes,
+    costChanges,
     bid,
     original,
     progress,
diff --git a/tools/est-test/native-extra.js b/tools/est-test/native-extra.js
index ca63a3650..66501a6d1 100644
--- a/tools/est-test/native-extra.js
+++ b/tools/est-test/native-extra.js
@@ -70,7 +70,17 @@ const EstExtra = (() => {
               number(row.TC),
               number(row.difference),
             ]),
-        ),
+        ) +
+          table(
+            ["원가 구분", "비목", "당초 금액", "변경 금액", "증감"],
+            EstBusiness.costChanges(project).map((row) => [
+              esc(row.Gubun),
+              esc(row.Name),
+              number(row.originalCost),
+              number(row.changedCost),
+              number(row.difference),
+            ]),
+          ),
         project.baseline
           ? `당초: ${esc(project.baseline.name)}. 당초 자료는 별도 사본으로 보존합니다.`
           : changes.some((row) => row.originalSource === "file")
diff --git a/tools/est-test/native-forms.js b/tools/est-test/native-forms.js
index 170392641..55f52545a 100644
--- a/tools/est-test/native-forms.js
+++ b/tools/est-test/native-forms.js
@@ -1,6 +1,11 @@
 const EstForms = (() => {
   const common = ["Code", "Name", "Size", "Unite"];
   function data(id, project, state = {}) {
+    if (id === "change-costs")
+      return {
+        columns: ["Gubun", "Name", "originalCost", "changedCost", "difference"],
+        rows: EstBusiness.costChanges(project),
+      };
     if (id === "annual-summary") {
       const output = EstBusiness.annual(project, false);
       return {
@@ -282,6 +287,8 @@ const EstForms = (() => {
     TotalCost: "누계 금액",
     adjustedCost: "조정 금액",
     excludedCost: "제외 금액",
+    originalCost: "당초 금액",
+    changedCost: "변경 금액",
     TargetCode: "연결 내역",
     TU: "단가",
     TC: "금액",
diff --git a/tools/est-test/native-report.js b/tools/est-test/native-report.js
index daf9b72d6..d062136ac 100644
--- a/tools/est-test/native-report.js
+++ b/tools/est-test/native-report.js
@@ -141,6 +141,7 @@ const EstReport = (() => {
       { Index: "escalation-summary", Name: "물가변동 내역서", Name2: "물가변동 내역서" },
       { Index: "escalation-costs", Name: "물가변동 원가계산서", Name2: "물가변동 원가계산서" },
       { Index: "annual-summary", Name: "연차 배분표", Name2: "연차 배분표" },
+      { Index: "change-costs", Name: "설계변경 원가 증감표", Name2: "설계변경 원가 증감표" },
     );
     const table = EstApp.state.project.tables[EstApp.state.view];
     const s = setting(),