The biggest pro to renting DVC points is simply that it is a way to stay at deluxe resorts for significantly lower prices than if you had gone through Disney, even with a room discount. You also will get free parking at the resort if you have a car (normally $25/day otherwise), and have the ability to book 1, 2 and 3 bedroom villas which is great if you're traveling with a large party. The biggest cons, however, are that your dates are locked in - you cannot change your dates or resort, technically the owner of the points can change the reservation and scam you (though I'd say it's unlikely), and you do not get daily housekeeping.
Whether you go through an owner or a third party website, it works the same way: Each DVC owner has points at a specific resort (some people own contracts at multiple resorts, but that's not really too relevant to this) and can book a room at that specific resort 11 months out. At the 7 month mark, a DVC owner can book a room at any resort. Depending on when you are going and where you are staying this will impact how you do things as some room types sell out before the 7 month mark - for example, a Beach Club studio during food and wine. In that case, you would need to secure the booking via points from a DVC owner at the specific resort so you could reserve it between 11-7 months.
To figure out pricing, you need to look at a
point chart (you can google this and find them through Disney, or David's
DVC rentals has an easy to use point calculator on their website) and see how many points your stay will cost. Then, depending on where you rent you'll pay a price per point - so number of points X price per point will get you your total.
We are renting DVC points for the first time next spring for a split stay at the Polynesian and Beach Club and personally went through a broker. It's cheaper to rent directly from an owner (though price per point will vary drastically), but there is some more security with a broker. One thing I did not realize though is this: We reached out to 3 different brokers that all had waiting lists for both Polynesian and Beach Club reservations at the 11 month mark because they did not have owners with points to fulfill our requests. This surprised me only because the brokers make it seem like as long as the room is physically available your request will be fulfilled. Obviously once I thought about how rentals work and the logistics it made sense, it's just that it wasn't really "advertised" on their websites that even if a room is available they might not be able to get the points to book it. In the end we found a broker that was slightly more expensive but was able to fulfill both reservations in 3 days and seeing as this is our honeymoon trip I was glad to pay the extra money to sleep better at night knowing they were booked lol! For what it's worth, should we have booked directly though Disney it would have been 2x as much money, and even if a room discount were to come out it still would've been thousands of dollars more.