diff --git a/.github/scripts/increment_build_number.sh b/.github/scripts/increment_build_number.sh
new file mode 100644
index 0000000..520455f
--- /dev/null
+++ b/.github/scripts/increment_build_number.sh
@@ -0,0 +1,8 @@
+export newVersion="$1"
+
+if [[ -n "$newVersion" ]]; then
+    #https://stackoverflow.com/a/30214769/13167574
+    perl -i -pe 's/^(version:\s+)(\d+\.\d+\.\d+)(\+)(\d+)$/$1.$ENV{'newVersion'}.$3.($4+1)/e' pubspec.yaml
+else
+    echo "argument error"
+fi
diff --git a/.github/scripts/stub_iap.sh b/.github/scripts/stub_iap.sh
new file mode 100644
index 0000000..210e1ea
--- /dev/null
+++ b/.github/scripts/stub_iap.sh
@@ -0,0 +1,2 @@
+# https://unix.stackexchange.com/questions/435708/regex-multiline-pattern-and-substitution-replacement
+perl -0777 -i -pe 's/(  m3_lightmeter_iap:\n)(    git:\n      url: "https:\/\/github.com\/vodemn\/m3_lightmeter_iap"\n      ref: main)/$1    path: iap/sg' pubspec.yaml
\ No newline at end of file
diff --git a/.github/workflows/build_apk.yml b/.github/workflows/build_apk.yml
index e61b38b..6acb464 100644
--- a/.github/workflows/build_apk.yml
+++ b/.github/workflows/build_apk.yml
@@ -27,6 +27,10 @@ jobs:
     runs-on: macos-11
     timeout-minutes: 15
     steps:
+      - uses: actions/checkout@v3
+        with:
+          submodules: recursive
+
       - name: Connect private iap package
         uses: webfactory/ssh-agent@v0.8.0
         if: ${{ inputs.include-iap }}
@@ -35,13 +39,8 @@ jobs:
 
       - name: Override iap package with stub
         if: ${{ !inputs.include-iap }}
-        run: | 
-          echo "\ndependency_overrides:\n  m3_lightmeter_iap:\n    path: iap" >> pubspec.yaml
-           
-      - uses: actions/checkout@v3
-        with:
-          submodules: recursive
-
+        run: bash ./.github/scripts/stub_iap.sh
+        
       - uses: actions/setup-java@v2
         with:
           distribution: "zulu"
diff --git a/.github/workflows/create_release.yml b/.github/workflows/create_release.yml
index e0281e3..69a672b 100644
--- a/.github/workflows/create_release.yml
+++ b/.github/workflows/create_release.yml
@@ -46,6 +46,10 @@ jobs:
     runs-on: macos-11
     timeout-minutes: 30
     steps:
+      - uses: actions/checkout@v3
+        with:
+          submodules: recursive
+
       - name: Connect private iap package
         uses: webfactory/ssh-agent@v0.8.0
         if: ${{ inputs.include-iap }}
@@ -54,12 +58,7 @@ jobs:
 
       - name: Override iap package with stub
         if: ${{ !inputs.include-iap }}
-        run: | 
-          echo "\ndependency_overrides:\n  m3_lightmeter_iap:\n    path: iap" >> pubspec.yaml
-
-      - uses: actions/checkout@v3
-        with:
-          submodules: recursive
+        run: bash ./.github/scripts/stub_iap.sh
 
       - uses: actions/setup-java@v3
         with:
@@ -98,7 +97,7 @@ jobs:
       # Therefore here we have to increment it as well to build an apk with the same build number.
       - name: Increment build number & replace version number
         if: ${{ inputs.github-release }}
-        run: perl -i -pe 's/^(version:\s+)(\d+\.\d+\.\d+)(\+)(\d+)$/$1."${{ github.event.inputs.version }}".$3.($4+1)/e' pubspec.yaml
+        run: bash ./.github/scripts/increment_build_number.sh ${{ github.event.inputs.version }}
 
       - name: Install Flutter
         uses: subosito/flutter-action@v2
@@ -160,7 +159,7 @@ jobs:
           submodules: recursive
 
       - name: Increment build number & replace version number
-        run: perl -i -pe 's/^(version:\s+)(\d+\.\d+\.\d+)(\+)(\d+)$/$1."${{ github.event.inputs.version }}".$3.($4+1)/e' pubspec.yaml
+        run: bash ./.github/scripts/increment_build_number.sh ${{ github.event.inputs.version }}
 
       - name: Commit changes
         run: |
diff --git a/.github/workflows/pr_check.yml b/.github/workflows/pr_check.yml
index e6f0294..70e6fa4 100644
--- a/.github/workflows/pr_check.yml
+++ b/.github/workflows/pr_check.yml
@@ -11,30 +11,25 @@ on:
   pull_request:
     branches: ["main"]
 
-env:
-  # Stub iap package if this worlflow is running from the PR from a fork
-  STUB_IAP: ${{ github.event.pull_request.head.repo.full_name != github.repository }}
-
 jobs:
   analyze_and_test:
     name: Analyze & test
     runs-on: macos-11
     timeout-minutes: 10
     steps:
+      - uses: actions/checkout@v3
+        with:
+          submodules: recursive
+
       - name: Connect private iap package
         uses: webfactory/ssh-agent@v0.8.0
-        if: !env.STUB_IAP
+        if: ${{ github.event.pull_request.head.repo.full_name == github.repository }}
         with:
           ssh-private-key: ${{ secrets.M3_LIGHTMETER_IAP_KEY }}
 
       - name: Override iap package with stub
-        if: env.STUB_IAP
-        run: |
-          echo "\ndependency_overrides:\n  m3_lightmeter_iap:\n    path: iap" >> pubspec.yaml
-
-      - uses: actions/checkout@v3
-        with:
-          submodules: recursive
+        if: ${{ github.event.pull_request.head.repo.full_name != github.repository }}
+        run: bash ./.github/scripts/stub_iap.sh
 
       - uses: subosito/flutter-action@v2
         with:
diff --git a/iap/lib/src/data/models/iap_product.dart b/iap/lib/src/data/models/iap_product.dart
index 706e3f1..ba24c17 100644
--- a/iap/lib/src/data/models/iap_product.dart
+++ b/iap/lib/src/data/models/iap_product.dart
@@ -1,5 +1,13 @@
+enum IAPProductStatus {
+  purchasable,
+  pending,
+  purchased,
+}
+
 enum IAPProductType { paidFeatures }
 
-class IAPProduct {
-  IAPProduct();
+abstract class IAPProduct {
+  const IAPProduct._();
+
+  IAPProductStatus get status => IAPProductStatus.purchasable;
 }
diff --git a/iap/lib/src/providers/iap_products_provider.dart b/iap/lib/src/providers/iap_products_provider.dart
index 4ea3c98..3014cd9 100644
--- a/iap/lib/src/providers/iap_products_provider.dart
+++ b/iap/lib/src/providers/iap_products_provider.dart
@@ -35,7 +35,7 @@ class IAPProducts extends InheritedModel<IAPProductType> {
     super.key,
   });
 
-  static IAPProduct? of(BuildContext context, IAPProductType type) => null;
+  static IAPProduct? productOf(BuildContext context, IAPProductType type) => null;
 
   static bool isPurchased(BuildContext context, IAPProductType type) => false;