The thing I tell people is that as a parent, you are going to put maybe a few hours into blocking them from getting to stuff. They are then going to spend as much time as they want trying to get through it. You can dig through concrete with a spoon if you’re patient enough.
Educate them, and give them access when they’re responsible enough
Also sounds like you had a crappy realtor. If you’re using a realtor, get them to work for you, that’s what they’re for. Give them the specs of the house you’re looking for, sure, but they should be calling you with listings, vetting the homes before they show them to you, handling negotiation relays and inspection setups, etc.
Just general advice, yes you pay them, but if they aren’t working for you, pay someone else.