Once you have renovated something within the village you use Design mode to change the choices you made anytime you want. 

To enter Design mode, tap the Design button (the one with the hammer on it, near the task button), or tap and hold on the village to see everything you can change. Here you can see all the choices you can redesign.

Tapping on one of them shows you all the options for that choice. Making a new choice cost coins, but once you have bought a new option it is unlocked for you forever. You can switch between unlocked options as often as you life.