This is a simple piggy bank inspired from the coin box of super mario. 

I've made a mechanism that ejects with a punch the top cover to retrive the coins/cash just like mario punching this box to take coins or power ups. If you dont want to destroy the 3d model with your punch you can still retrive the money collected by simply takeing off the cover, because there are 4 slots, located on the box and the cover, to insert the magnets 

All the tollerances are 0.3mm even for the question marks.

Assembly proccess:

It's simple all you need to do is to have a glue and 8 magnets (6mm in diameter x 3mm in height), just put the glue on all the parts and insert it and wait till it dry.

Print tips:

For bambulabs I think you can print everything without supports but since I dont have one, I printed with supports only for the box to have perfect bridges for the question marks. Other than that you can print the remaining parts without supports