Fools build houses, and wise men buy them.

The saying contrasts the expense and trouble of creating something from scratch with the advantage of acquiring it after someone else has done the hard work.

It presents the buyer as shrewd not because building is always foolish, but because a completed house may be obtained more conveniently or advantageously.

Use it humorously or critically when someone takes on the costly work of building or creating something that another person can later acquire more easily.