How can my charachter buy an apartmant? (IN GAME)

Hello everyone.

I’m making a simulation game. My character can earn money from NPCs.

my question is: how can my character buy an apartment in the game with his own money?

A helpful answer, picture or video would be really helpful.

(UE4-27 Vers.)

Think about what is stopping the character from entering the apartment. Buying = removing that obstacle. It can be a simple boolean value, it can be a blocking volume that gets destroyed or disabled.