You can buy "re-sale" from an exisitng member usually through a resale broker such as the The Timeshare Store which is a sponsor of this site and you can view what it has avaialble by just going to the top of the page you are on now and click on The Timeshare Store. Current asking prices for BWV are in the $82 range.
Alternatively, you can buy "new" from Disney, even though it is a previously sold out resort like BWV, because Disney gets points back via right of first refusal or foreclosures. It takes trhe points and puts them back into the system for sale and thus can sell them new again in any allowed increments, e.g., if it gets back from an owner a 200 point contract it can sell those as eight new and separate 25 point contracts. The current price through Disney for Boardwalk points is $155, i.e., 89% higher than the resale market.
If you buy resale from another member, you will have to go through Disney's right of first refusal, which allows it to buy the contract for the same price that you offer the seller, with the result that you gain nor lose anything other than the time spent doing the resale. In the majority of cases Disney waives ROFR and allows the resale to occur. Also,a resale purchaser has to wait until after closing to get into the
DVC system and be able to reserve and that can take up to a few weeks after closing. As a resale purchaser you will not have the ability to use those points for trading out to the Disney Collections: non-DVC Disney Hotels (other than at
Disneyland), the Cruise, the Disney Adventures or the Disney concierge collection hotels. That is a perk for purchasers from Disney that could be taken away from them at any time and is not considered by most existing members to be of any real value including because the points needed for those trade outs are already high and can and usually do increase annually. Otherwise, you will be just like any other member, able to reserve DVC rooms or trade out through RCI.
If instead you choose to go through Disney, the process will be quiicker, easy to get but high interest financing is available, you can use the Disney Collections and you will be able to make a DVC reservation with the new points for a time after closing right after you agree to purchase. In other words, for the benefit of having an easier process, easy to get high financing, and having the Disney Collections as a possible trade out, you only have to pay an extra $73 a point buying from Disney rather than through resale.