To get a feel for cost price out your vacation on line, ideally for the same time of year, in several different resorts that appeal to you, then decide which is comfortable budget wise for you. Remember tickets cost a fortune, food isn't cheap, it's an expensive vacation. Become familiar with discounts and whether Disney typically offers any during the time of year you plan to go. There are very few times when there aren't some kinds of discounts offered. WDW is huge. There is no way to be conveniently close to all parks.
Least costly: the AllStars resorts - but with 5 in the family only the pricier suites or 2 rooms are an option.
Mid range: 2 of these offer rooms for families of 5 CBR and POR. Both lovely, well themed resorts. POR has a boat to DTD.
Deluxes:
Cheapest - WL and AKL, but I don't think either sleep 5
Moderate- BC, YC, BWI. Easy access to 2 parks -Epcot & DHS. BC & YC have the awesome storm along bay swimming area, both sleep 5, I'm not sure about BW occupancy levels.
Expensive - Contemporary, Poly and GF, in that order. On the monorail, Contemporary you can walk to the MK.
Regarding renting points:
1) There is risk, whether you go through an owner or a broker, you risk having your reservation canceled by the owner intentionally (eg just because or they decide to sell their points) or negligently (eg the owner doesn't pay their dues or their loan causing
DVC to cancel any reservations they've made.)
2) you must plan early - like 11 months early for popular times/resorts.
3) you must pay all of your room cost up front when you reserve (note, some private renters are more flexible about this.)
4) limited housekeeping (4th day on 8 day stays.)
5) no flexibility - no changes, need to arrive a day later - can't usually do that. Have an emergency, Disney will refund all or most of your money or let you reschedule, a DVC rental won't allow that.
6) 4 pm check in, and due to high DVC occupancy early check in is much less common than with a Disney reservation.
People assume these risks because DVC renting
can save money. But sometimes the Disney discounts are almost as good of a deal, so you have to run the numbers if you are interested in renting DVC points to see whether the savings are worth the risks.