diff --git a/MLTraining/train.py b/MLTraining/train.py
index c8871c2..ce716db 100644
--- a/MLTraining/train.py
+++ b/MLTraining/train.py
@@ -19,6 +19,12 @@
 HANGUL_BASE = 0xAC00
 HANGUL_LAST = 0xD7A3
 
+# 한글 외 문자: 숫자, 영문 대소문자, 상호명에 흔히 쓰이는 특수문자
+DIGITS = list("0123456789")
+ALPHA_LOWER = list("abcdefghijklmnopqrstuvwxyz")
+ALPHA_UPPER = list("ABCDEFGHIJKLMNOPQRSTUVWXYZ")
+MISC_CHARS = [" ", "&", "+", "-", ".", ",", "'"]
+
 
 def decompose_hangul(char):
     """완성형 한글 한 글자를 (초성, 중성, 종성) 튜플로 분해한다. 한글이 아니면 None."""
@@ -48,12 +54,11 @@ def tokenize(text):
     return tokens
 
 
-def build_vocabulary(memos):
-    """시드 데이터에 등장하는 모든 자모/문자를 모아 정렬된 vocabulary를 만든다."""
-    tokens = set()
-    for memo in memos:
-        tokens.update(tokenize(memo))
-    return sorted(tokens)
+def build_vocabulary():
+    """이론상 가능한 전체 자모와 비한글 문자를 고정된 vocabulary로 만든다."""
+    jongsung_tokens = ["_" + j for j in JONGSUNG if j]  # 종성 없음("") 제외
+    tokens = CHOSUNG + JUNGSUNG + jongsung_tokens + DIGITS + ALPHA_LOWER + ALPHA_UPPER + MISC_CHARS
+    return sorted(set(tokens))
 
 
 def vectorize(memo, vocabulary):
@@ -69,7 +74,7 @@ def main():
     memos = [item["memo"] for item in seed_data]
     labels = [item["category"] for item in seed_data]
 
-    vocabulary = build_vocabulary(memos)
+    vocabulary = build_vocabulary()
     print(f"Vocabulary 크기: {len(vocabulary)}개 (자모/문자 단위)")
 
     vectors = [vectorize(memo, vocabulary) for memo in memos]
diff --git a/SpendLearning/SpendLearning/Resource/CategoryClassifier.mlmodel b/SpendLearning/SpendLearning/Resource/CategoryClassifier.mlmodel
index 84558c7..3c78442 100644
Binary files a/SpendLearning/SpendLearning/Resource/CategoryClassifier.mlmodel and b/SpendLearning/SpendLearning/Resource/CategoryClassifier.mlmodel differ
diff --git a/SpendLearning/SpendLearning/Resource/vocabulary.json b/SpendLearning/SpendLearning/Resource/vocabulary.json
index 92a23a3..e464a8a 100644
--- a/SpendLearning/SpendLearning/Resource/vocabulary.json
+++ b/SpendLearning/SpendLearning/Resource/vocabulary.json
@@ -1,7 +1,11 @@
 [
   " ",
   "&",
+  "'",
   "+",
+  ",",
+  "-",
+  ".",
   "0",
   "1",
   "2",
@@ -9,47 +13,88 @@
   "4",
   "5",
   "6",
+  "7",
+  "8",
+  "9",
   "A",
+  "B",
   "C",
+  "D",
+  "E",
+  "F",
   "G",
   "H",
   "I",
+  "J",
   "K",
   "L",
   "M",
   "N",
   "O",
   "P",
+  "Q",
   "R",
   "S",
   "T",
   "U",
   "V",
+  "W",
   "X",
+  "Y",
+  "Z",
   "_ㄱ",
   "_ㄲ",
+  "_ㄳ",
   "_ㄴ",
+  "_ㄵ",
+  "_ㄶ",
+  "_ㄷ",
   "_ㄹ",
+  "_ㄺ",
+  "_ㄻ",
+  "_ㄼ",
+  "_ㄽ",
+  "_ㄾ",
+  "_ㄿ",
+  "_ㅀ",
   "_ㅁ",
   "_ㅂ",
+  "_ㅄ",
   "_ㅅ",
+  "_ㅆ",
   "_ㅇ",
+  "_ㅈ",
   "_ㅊ",
+  "_ㅋ",
   "_ㅌ",
+  "_ㅍ",
+  "_ㅎ",
   "a",
   "b",
   "c",
   "d",
   "e",
+  "f",
   "g",
   "h",
   "i",
+  "j",
   "k",
+  "l",
+  "m",
   "n",
+  "o",
+  "p",
+  "q",
   "r",
   "s",
   "t",
   "u",
+  "v",
+  "w",
+  "x",
+  "y",
+  "z",
   "ㄱ",
   "ㄲ",
   "ㄴ",
@@ -72,6 +117,7 @@
   "ㅏ",
   "ㅐ",
   "ㅑ",
+  "ㅒ",
   "ㅓ",
   "ㅔ",
   "ㅕ",
@@ -89,4 +135,4 @@
   "ㅡ",
   "ㅢ",
   "ㅣ"
-]
+]
\ No newline at end of file
diff --git a/SpendLearning/SpendLearning/Source/Data/Predictors/CategoryPredictor.swift b/SpendLearning/SpendLearning/Source/Data/Predictors/CategoryPredictor.swift
index f4a5ec7..306ed82 100644
--- a/SpendLearning/SpendLearning/Source/Data/Predictors/CategoryPredictor.swift
+++ b/SpendLearning/SpendLearning/Source/Data/Predictors/CategoryPredictor.swift
@@ -113,14 +113,18 @@ private extension CategoryPredictor {
         let writableURL = supportDir.appendingPathComponent("CategoryClassifier.mlmodelc")
         self.modelURL = writableURL
 
-        guard let bundledCompiledURL = Bundle.main.url(forResource: "CategoryClassifier", withExtension: "mlmodelc") else {
+        // 이미 온디바이스로 학습된 사본이 있으면 그대로 사용해 학습 결과를 보존한다.
+        // 최초 설치 등으로 사본이 없을 때만 번들 모델을 복사한다.
+        if fileManager.fileExists(atPath: writableURL.path) {
             self.model = try? MLModel(contentsOf: writableURL)
             return
         }
 
-        try? fileManager.removeItem(at: writableURL)
-        try? fileManager.copyItem(at: bundledCompiledURL, to: writableURL)
+        guard let bundledCompiledURL = Bundle.main.url(forResource: "CategoryClassifier", withExtension: "mlmodelc") else {
+            return
+        }
 
+        try? fileManager.copyItem(at: bundledCompiledURL, to: writableURL)
         self.model = try? MLModel(contentsOf: writableURL)
     }
 
diff --git a/SpendLearning/SpendLearning/Source/Presentation/View/NewExpense/ExpenseInputViewController.swift b/SpendLearning/SpendLearning/Source/Presentation/View/NewExpense/ExpenseInputViewController.swift
index 9da033b..08ab2fe 100644
--- a/SpendLearning/SpendLearning/Source/Presentation/View/NewExpense/ExpenseInputViewController.swift
+++ b/SpendLearning/SpendLearning/Source/Presentation/View/NewExpense/ExpenseInputViewController.swift
@@ -26,6 +26,7 @@ final class ExpenseInputViewController: UIViewController {
 
     private let amountFieldLabel = UILabel()
     private let amountTextField = UITextField()
+    private let amountUnitLabel = UILabel()
     private let amountSeparator = UIView()
 
     private let memoFieldLabel = UILabel()
@@ -92,7 +93,7 @@ private extension ExpenseInputViewController {
         let digitsOnly = (amountTextField.text ?? "").filter { $0.isNumber }
         let amount = Int(digitsOnly) ?? 0
         viewModel.didInputAmount(amount)
-        amountTextField.text = amount == 0 ? "" : "\(amount.formatted())원"
+        amountTextField.text = amount == 0 ? "" : amount.formatted()
     }
 }
 
@@ -167,16 +168,20 @@ private extension ExpenseInputViewController {
         amountFieldLabel.font = .systemFont(ofSize: 13, weight: .regular)
         amountFieldLabel.textColor = .DesignSystem.subtitle
 
-        amountTextField.text = viewModel.initialAmount == 0 ? "" : "\(viewModel.initialAmount.formatted())원"
+        amountTextField.text = viewModel.initialAmount == 0 ? "" : viewModel.initialAmount.formatted()
         amountTextField.placeholder = "0"
         amountTextField.font = .systemFont(ofSize: 20, weight: .semibold)
         amountTextField.textColor = .DesignSystem.primary
         amountTextField.keyboardType = .numberPad
         amountTextField.addTarget(self, action: #selector(amountDidChange), for: .editingChanged)
 
+        amountUnitLabel.text = "원"
+        amountUnitLabel.font = .systemFont(ofSize: 20, weight: .semibold)
+        amountUnitLabel.textColor = .DesignSystem.primary
+
         amountSeparator.backgroundColor = .DesignSystem.separator
 
-        [amountFieldLabel, amountTextField, amountSeparator].forEach {
+        [amountFieldLabel, amountTextField, amountUnitLabel, amountSeparator].forEach {
             $0.translatesAutoresizingMaskIntoConstraints = false
             cardView.addSubview($0)
         }
@@ -236,7 +241,10 @@ private extension ExpenseInputViewController {
 
             amountTextField.topAnchor.constraint(equalTo: amountFieldLabel.bottomAnchor, constant: 4),
             amountTextField.leadingAnchor.constraint(equalTo: cardView.leadingAnchor, constant: 16),
-            amountTextField.trailingAnchor.constraint(equalTo: cardView.trailingAnchor, constant: -16),
+            amountTextField.trailingAnchor.constraint(equalTo: amountUnitLabel.leadingAnchor, constant: -4),
+
+            amountUnitLabel.firstBaselineAnchor.constraint(equalTo: amountTextField.firstBaselineAnchor),
+            amountUnitLabel.trailingAnchor.constraint(equalTo: cardView.trailingAnchor, constant: -16),
 
             amountSeparator.topAnchor.constraint(equalTo: amountTextField.bottomAnchor, constant: 16),
             amountSeparator.leadingAnchor.constraint(equalTo: cardView.leadingAnchor, constant: 16),