I know it's boring but worth doing some maths.
One thing I didn't factor in when buying was massive fluctuations in exchange rate. Rate was up to 2:1 a long time ago, then seemed to be stuck about 1.6:1, now it's low at 1.2:1 (pretty bad time to buy atm)
Where/when/what room do you want to stay?
Let's say early July in standard view studio.
Animal Kingdom Lodge 200pts
Polynesian 292pts
That means about 100pts is needed as long as banking and borrowing remain at 100%
New
DVC buyers have to get a minimum of 150pts from Disney or what I would recommend is you can get 100pts on the resale market. Blended average of all resorts is about $135 so it will cost about £10-12k depending on resort, whether you are paying this years dues and legal closing costs.
Don't buy a 2042 expiry resort as they will drop in value in next 5 years.
As mentioned above a 3 year gap is going to mean some risk of losing points or having to buy some One Time Use points to match a reservation.
If you don't want hassle of owning you could just rent.
After 10 years you could well be able to sell your contract at a price which means you paid nothing for 10 years of vacation although it's not guaranteed and market is overrun with sellers atm.