Resales: You can save money (generally 15% - 25% depending on the resort, contract size, bank/borrow/current year points and terms). You may end up buying a contract larger than you really want, so the savings may be consumed in more points and the associated maintenance fees over time. Everything is negotiable, just like any real estate contract. You must buy the contract as is (ie. a seller cannot split a contract -- but add-on contracts may be sold separately from the master contract). There are usually contracts for all of the resorts, except the newest ones, on the market. You must close before reservations can be made. You need to pay a bit more attention to how the contract is worded, then you do with Disney -- be very specific about what you are buying and who is paying what. If you do not have the cash to buy, there is one organization that I am aware of who lends for timeshares -- I have no experience with them. Otherwise you would need to arrange your own financing.
Direct: You determine the size of the contract and may be able to select your use year. Nothing is negotiable, except sometimes Disney offers Magical Beginnings (a program to buy back your first year's points -- the amount is set by Disney for each resort and they change it often). Disney always pays the closing costs. Financing through Disney is easy, but expensive (but no more than any timeshare would be). You can make reservations as soon as you make your deposit. Maintenance fees are pro rated from the date of contract, not date of closing. You can buy into the newest resorts, but may need to waitlist for other resorts.
We bought OKW resale and BCV direct at about the same time. There was very little difference in the time period from offer to closing. We used Pat at The Timeshare Store. She was professional, efficient and very knowledgable (formerly associated with
DVC). Byron is our DVC guide. The guides are very low key, no hype or pressure. They take whatever time you need to learn about DVC and make your decsion. Byron is a classic gentleman, returns calls promptly, even when on holiday. We highly recommend both.