During the ACP FO portion, the pilot doesn't relocate. They live wherever and we fly them to their assignment (one of our high timed routes).
When they become a full BE99 Captain at 1,200 TT, the pilot will pick an available base. If they don't live near it, they will have to relocate.
We have a relocation assistance program. It's a set amount, so probably wouldn't cover all expenses, but it helps.