Just a very simple and quick tip
Cardboard boxes can be used for EVERYTHING! My daughter, who is almost 3 years old, is responsible for the painting, and how the windows and doors should be. Old "Christmas lights" taped to the ceiling.
A very fun process for the little ones to take part in, and Babyborn was very happy too! Some people might play more with cars, can be made into a garage and car wash, for example. Or Dinosaur caves ETC. Just hope all children who are at home now are allowed to be creative! Cheap, fun and simple ideas!