diff --git a/client/components/tracker/DriftInsightPanel.jsx b/client/components/tracker/DriftInsightPanel.tsx
similarity index 95%
rename from client/components/tracker/DriftInsightPanel.jsx
rename to client/components/tracker/DriftInsightPanel.tsx
index 1d84bac..6ad6943 100644
--- a/client/components/tracker/DriftInsightPanel.jsx
+++ b/client/components/tracker/DriftInsightPanel.tsx
@@ -1,13 +1,15 @@
-import React, { useState } from 'react';
+import { useState } from 'react';
 import { TrendingUp, TrendingDown, ChevronDown } from 'lucide-react';
 import { toast } from 'sonner';
 import { api } from '@/api';
 import { cn, fmt } from '@/lib/utils';
+import { asDollars } from '@/lib/money';
 import { Button } from '@/components/ui/button';
 import { Badge } from '@/components/ui/badge';
 import { Collapsible, CollapsibleTrigger, CollapsibleContent } from '@/components/ui/collapsible';
+import type { DriftBill } from '@/types';
 
-function DriftRow({ row, refresh }) {
+function DriftRow({ row, refresh }: { row: DriftBill; refresh: () => void }) {
   const [loading, setLoading] = useState(false);
 
   async function handleUpdate() {
@@ -131,7 +133,7 @@ function DriftRow({ row, refresh }) {
   );
 }
 
-export default function DriftInsightPanel({ driftBills, refresh }) {
+export default function DriftInsightPanel({ driftBills, refresh }: { driftBills?: DriftBill[]; refresh: () => void }) {
   const [isOpen, setIsOpen] = useState(true);
 
   if (!driftBills?.length) return null;
@@ -159,7 +161,7 @@ export default function DriftInsightPanel({ driftBills, refresh }) {
                   : `${driftBills.length} bills changed price`}
               </span>
               <span className={cn('font-mono text-sm', netColor)}>
-                {sign}{fmt(Math.abs(totalNetDelta))}/mo net
+                {sign}{fmt(asDollars(Math.abs(totalNetDelta)))}/mo net
               </span>
             </div>
             <ChevronDown
diff --git a/client/components/tracker/OverdueCommandCenter.jsx b/client/components/tracker/OverdueCommandCenter.tsx
similarity index 89%
rename from client/components/tracker/OverdueCommandCenter.jsx
rename to client/components/tracker/OverdueCommandCenter.tsx
index d4d111d..0787d22 100644
--- a/client/components/tracker/OverdueCommandCenter.jsx
+++ b/client/components/tracker/OverdueCommandCenter.tsx
@@ -1,8 +1,9 @@
-import React, { useState } from 'react';
+import { useState } from 'react';
 import { AlertCircle, ChevronDown, BellOff, SkipForward, CreditCard } from 'lucide-react';
 import { toast } from 'sonner';
 import { api } from '@/api';
 import { cn, fmt, localDateString } from '@/lib/utils';
+import { asDollars } from '@/lib/money';
 import { Button } from '@/components/ui/button';
 import { Badge } from '@/components/ui/badge';
 import { Collapsible, CollapsibleTrigger, CollapsibleContent } from '@/components/ui/collapsible';
@@ -12,24 +13,33 @@ import {
   DropdownMenuContent,
   DropdownMenuItem,
 } from '@/components/ui/dropdown-menu';
+import type { TrackerRow } from '@/types';
 
-function snoozeUntil(days) {
+function snoozeUntil(days: number): string {
   const d = new Date();
   d.setDate(d.getDate() + days);
   return localDateString(d);
 }
 
-function daysOverdueLabel(dueDate) {
+function daysOverdueLabel(dueDate: string | null | undefined): string {
   if (!dueDate) return 'overdue';
   const today = new Date();
   today.setHours(0, 0, 0, 0);
   const due = new Date(`${dueDate}T00:00:00`);
-  const days = Math.floor((today - due) / 86_400_000);
+  const days = Math.floor((today.getTime() - due.getTime()) / 86_400_000);
   if (days <= 0) return 'due today';
   return `${days} ${days === 1 ? 'day' : 'days'} overdue`;
 }
 
-function OverdueRow({ row, year, month, onPayNow, onRefresh }) {
+interface OverdueRowProps {
+  row: TrackerRow;
+  year: number;
+  month: number;
+  onPayNow: (row: TrackerRow) => void;
+  onRefresh: () => void;
+}
+
+function OverdueRow({ row, year, month, onPayNow, onRefresh }: OverdueRowProps) {
   const [loading, setLoading] = useState(false);
   const threshold = row.actual_amount ?? row.expected_amount;
 
@@ -51,7 +61,7 @@ function OverdueRow({ row, year, month, onPayNow, onRefresh }) {
     }
   }
 
-  async function handleSnooze(days) {
+  async function handleSnooze(days: number) {
     setLoading(true);
     try {
       await api.snoozeOverdue(row.id, {
@@ -141,7 +151,15 @@ function OverdueRow({ row, year, month, onPayNow, onRefresh }) {
   );
 }
 
-export default function OverdueCommandCenter({ rows, year, month, refresh, onPayNow }) {
+interface OverdueCommandCenterProps {
+  rows: TrackerRow[];
+  year: number;
+  month: number;
+  refresh: () => void;
+  onPayNow: (row: TrackerRow) => void;
+}
+
+export default function OverdueCommandCenter({ rows, year, month, refresh, onPayNow }: OverdueCommandCenterProps) {
   const todayStr = localDateString();
   const [isOpen, setIsOpen] = useState(true);
 
@@ -181,7 +199,7 @@ export default function OverdueCommandCenter({ rows, year, month, refresh, onPay
               </span>
               {overdueRows.length > 0 && (
                 <span className="font-mono text-sm text-rose-400 dark:text-rose-300">
-                  {fmt(totalOverdue)}
+                  {fmt(asDollars(totalOverdue))}
                 </span>
               )}
             </div>
diff --git a/client/types.ts b/client/types.ts
index 2e63693..383ff3b 100644
--- a/client/types.ts
+++ b/client/types.ts
@@ -14,6 +14,19 @@ import type { Dollars } from '@/lib/money';
 export type TrackerStatus =
   | 'paid' | 'autodraft' | 'upcoming' | 'due_soon' | 'late' | 'missed' | 'skipped';
 
+// A price-drift finding (driftService.getDriftReport) — a bill whose recent
+// payments trend away from its expected amount.
+export interface DriftBill {
+  id: number;
+  name: string;
+  category_name?: string | null;
+  expected_amount: Dollars;
+  recent_amount: Dollars;
+  direction: string;
+  drift_pct: number;
+  months_sampled: number;
+}
+
 // A suggested autopay payment (trackerService.applyAutopaySuggestions).
 export interface AutopaySuggestion {
   bill_id: number;