The house allows the production of coins, but can be built, when this house is built, which was built the first time it will increase the coin.
You can also improve the house, it allows you to increase the coins.
Engine & Engine Upgrade • Cogwheel & Big Cogwheel •
Hammer & Hammer Upgrade • Money Machine Upgrade & Interest Rate •
Balloon Pump & Balloon Pump Upgrade & Balloon Speed •
Portal & Portal Amplifier & Charger Upgrade •
Mine • Selling Detail
House & Tavern & Building Upgrade • Planet & Planet Upgrade •
Tower • Windmill & Bellow & Bellow Upgrade • Propeller •
Tax Collector & Tax Collector Upgrade • Crystal & Crystal Upgrade