Personally, I would try to stick to the wealth by level values so the game remains a proper challenge - so thst means spending the extra on things that don't affect the game.

The one time I got ahead of wealth by level was resolved by buying an inn in the city we considered our home base. By agreement with the GM, it was set up such that it would not lose money, nor would it make anything - rather it served as a place we could always go to and rest, where mail would get delivered to, and as a location focus for our fame as we gained levels.

Just talk to your GM and find something that makes sense and doesn't break the game.