All the credits for this great model goes to Reno77. This is a remix from https://www.thingiverse.com/thing:2502026 If you just want the model or a cup, look there.

The Piggybank is a little bigger (150 mm), hollowed (wall 2.4 mm), coin-slot (35x3.5) and a threaded opening (https://www.thingiverse.com/thing:3383689) at the bottom are added.

Supports at the outside are needed. The roof is already supported with a dome inside. The bottom in this version is also rounded inside to prevent the visible layerline at the bottom you see in the photo's. A new photo is added of a second print of the model as presented here where that annoying layerline is missing.

Happy Saving.