How can i use datastores to let the server know the player owns a house in the game?

how could I do this?

If its a house that only 1 person can own permanently, you could att a datastore for an objectvalue, its value coould be the house. Save it and load it when the player joins again and check if the players owns a house, if the player does, send that information to wherever you want.

I have a string value that updates when a player buys a house. the data it saves is the player's actual name how do I save a string value in a datastore and load it back in when the player joins so they don't have to buy the house again?