Alot will depend on how long Disney reviews it. But I would say 8-12 weeks
from the time the offer is accepted.
The process in brief.
If you are working with a realtor.
You find a listing.
You make an offer.
If seller accepts, you put a deposit.
Realtor gathers info and sends to Disney.
Disney reviews it. If they do not excerise their ROFR rights. They send it back to the realtor.
Realtor sets closing and performs more paperwork.
You send them money
Property closes they send the seller money.
You will get a deed and then you can book a vacation.
Expect 8-12 weeks before you can call disney for a vacation.