diff --git a/lib/blnk/balance.rb b/lib/blnk/balance.rb
index 4ca7f44..e35c1cb 100644
--- a/lib/blnk/balance.rb
+++ b/lib/blnk/balance.rb
@@ -4,8 +4,8 @@ module Blnk
   # Balance representation
   class Balance < Resourceable
     def self.resource_name = :balances
+    def self.id_field = :balance_id
 
-    def persisted? = !balance_id.nil?
     def body_data = { ledger_id:, currency: }
   end
 end
diff --git a/lib/blnk/ledger.rb b/lib/blnk/ledger.rb
index 815a78c..e7b5baf 100644
--- a/lib/blnk/ledger.rb
+++ b/lib/blnk/ledger.rb
@@ -4,8 +4,8 @@ module Blnk
   # Ledger representation
   class Ledger < Resourceable
     def self.resource_name = :ledgers
+    def self.id_field = :ledger_id
 
-    def persisted? = !ledger_id.nil?
     def body_data = { name:, meta_data: }
   end
 end
diff --git a/lib/blnk/resourceable.rb b/lib/blnk/resourceable.rb
index 214a755..637c0b9 100644
--- a/lib/blnk/resourceable.rb
+++ b/lib/blnk/resourceable.rb
@@ -7,47 +7,50 @@ class SearchResult < OpenStruct; end
 
     include Client
 
-    def self.resource_name = raise NotImplementedError
+    class << self
+      def resource_name = raise NotImplementedError
+      def id_field = :id
 
-    def self.find(id)
-      response = new.get_request(path: "/#{resource_name}/#{id}")
-      return response unless response.status.success?
+      def find(id)
+        response = new.get_request(path: "/#{resource_name}/#{id}")
+        return response unless response.status.success?
 
-      new response.parse
-    end
+        new response.parse
+      end
 
-    def self.all
-      response = new.get_request(path: "/#{resource_name}")
-      return response unless response.status.success?
+      def all
+        response = new.get_request(path: "/#{resource_name}")
+        return response unless response.status.success?
 
-      response.parse.map do |r|
-        new r
+        response.parse.map do |r|
+          new r
+        end
       end
-    end
 
-    def self.create(*)
-      response = new.post_request(
-        path: "/#{resource_name}",
-        body: new(*).body_data
-      )
-      return response unless response.status.success?
+      def create(**args)
+        response = new.post_request(
+          path: "/#{resource_name}",
+          body: args
+        )
+        return response unless response.status.success?
 
-      new(response.parse)
-    end
+        new(response.parse)
+      end
 
-    def self.search(**args)
-      response = new.post_request(
-        path: "/search/#{resource_name}",
-        body: args
-      )
-      return response unless response.status.success?
+      def search(**args)
+        response = new.post_request(
+          path: "/search/#{resource_name}",
+          body: args
+        )
+        return response unless response.status.success?
 
-      sr = SearchResult.new(response.parse)
-      sr.resource_name = resource_name
-      sr
+        sr = SearchResult.new(response.parse)
+        sr.resource_name = resource_name
+        sr
+      end
     end
 
-    def persisted? = raise NotImplementedError
+    def persisted? = table[self.class.id_field]
     def body_data = raise NotImplementedError
   end
 end
diff --git a/lib/blnk/transaction.rb b/lib/blnk/transaction.rb
index 5624bbe..308b2eb 100644
--- a/lib/blnk/transaction.rb
+++ b/lib/blnk/transaction.rb
@@ -4,8 +4,8 @@ module Blnk
   # Transaction representation
   class Transaction < Resourceable
     def self.resource_name = :transactions
+    def self.id_field = :transaction_id
 
-    def persisted? = !transaction_id.nil?
     def body_data = {}
   end
 end
diff --git a/test/blnk/test_transaction.rb b/test/blnk/test_transaction.rb
new file mode 100644
index 0000000..426b257
--- /dev/null
+++ b/test/blnk/test_transaction.rb
@@ -0,0 +1,111 @@
+# frozen_string_literal: true
+
+require 'test_helper'
+
+def stub_find_transaction_request_with_error
+  stub_request(:get, %r{/transactions/(.*)})
+    .to_return_json(body: { error: 'balance with ID \'transaction_id\' not found' }, status: 400)
+end
+
+def transaction_response_body # rubocop:disable Metrics/MethodLength
+  {
+    precise_amount: 7500,
+    amount: 75,
+    rate: 0,
+    precision: 100,
+    transaction_id: 'txn_bb8e13c5-1d16-4e94-add7-efd377fd551a',
+    parent_transaction: '',
+    source: 'bln_216507cb-2fb1-4238-a184-805c455f8fe2',
+    destination: 'bln_469f93bc-40e9-4e0e-b6ab-d11c3638c15d',
+    reference: 'ref_005',
+    currency: 'BRLX',
+    description: 'For fees',
+    status: 'QUEUED',
+    hash: '74a2fecf01e73a31c005ce3bd840d285edce87e3bdb3e0ed99e0af124a6165f8',
+    allow_overdraft: true,
+    inflight: false,
+    created_at: '2024-06-27T20:23:17.737289826Z',
+    scheduled_for: '0001-01-01T00:00:00Z',
+    inflight_expiry_date: '0001-01-01T00:00:00Z'
+  }
+end
+
+def stub_find_transaction_request_with_success
+  stub_request(:get, %r{/transactions/(.*)})
+    .to_return_json(body: transaction_response_body, status: 200)
+end
+
+def stub_create_transaction_request_with_success
+  stub_request(:post, %r{/transactions})
+    .to_return_json(body: transaction_response_body, status: 200)
+end
+
+def stub_create_transaction_request_with_error
+  stub_request(:post, %r{/transactions})
+    .to_return_json(body: { error: 'missing transaction_id' }, status: 400)
+end
+
+# NOTE: This route does not exists, at least for now
+def stub_all_transaction_request_with_error
+  stub_request(:get, %r{/transactions})
+    .to_return_json(body: { error: 'internal_server_error' }, status: 500)
+end
+
+def stub_all_transaction_request_with_success
+  stub_request(:get, %r{/transactions})
+    .to_return_json(body: [transaction_response_body], status: 200)
+end
+
+class TestTransaction < Minitest::Test
+  def test_that_transaction_not_found
+    stub_find_transaction_request_with_error
+    find = Blnk::Transaction.find 'transaction_id'
+
+    assert find.status.bad_request?
+  end
+
+  def test_that_transaction_find_success
+    stub_find_transaction_request_with_success
+    find = Blnk::Transaction.find 'transaction_id'
+
+    assert find.is_a?(Blnk::Transaction)
+    assert find.transaction_id.eql?(transaction_response_body[:transaction_id])
+  end
+
+  # NOTE: /transactions route does not exist, at moment
+  # def test_that_transaction_all_error
+  #   stub_all_transaction_request_with_error
+
+  #   all = Blnk::Transaction.all
+
+  #   assert !all.status.success?
+  # end
+
+  # def test_that_transaction_all_success
+  #   stub_all_transaction_request_with_success
+
+  #   all = Blnk::Transaction.all
+
+  #   assert all.is_a?(Array)
+  #   assert all.first.is_a?(Blnk::Transaction)
+  #   assert all.first.transaction_id.eql?(transaction_response_body[:transaction_id])
+  # end
+
+  def test_that_transaction_create_errosr
+    stub_create_transaction_request_with_error
+
+    create = Blnk::Transaction.create
+
+    assert create.status.bad_request?
+  end
+
+  def test_that_transaction_create_success
+    stub_create_transaction_request_with_success
+
+    create = Blnk::Transaction.create(ledger_id: 'ledger_id', currency: 'USD')
+
+    assert create.is_a?(Blnk::Transaction)
+    assert create.transaction_id.eql?(transaction_response_body[:transaction_id])
+    assert create.name.eql?(transaction_response_body[:name])
+  end
+end