It's locked permanently because some retarded f*ck working at R* decided it would be a good idea to block out every interior used in missions for free roam.
You're kidding. I was just inside the damn thing, what's the point of locking it out?
So really, I just bought a $2,000,000 place for nothing.
Yep. Every property in the game is a waste (there's no interiors, and it takes like 80 in game weeks to make your money back). I even bought the Golf Club and the only thing they let you do is play golf with any clothes you want...
Wow. What a waste of time.
So the only point of property is to make some money that you have no real use for other than clothes, cars and other stuff.
Seriously, what is the point of locking out the interiors when we were just in them? That's just asinine. What insipid troglodyte thought this was a good idea?