My Reponse:
I will assume that you are talking about the weekend before July 4th or the weekend after, because July 4th falls on a Wednesday this year.
I am also assuming that you are talking about Wyndham Seawatch Plantation at North Myrtle Beach, SC.
With those two assumptions in mind, an owner who chooses to rent is going to want to recover his or her maintenance fee for the days rented and probably at least a 50% premium over those maintenance fees.
In order for an owner of points to get access to the Myrtle Beach Resorts during the time frame you are talking about, the owner would have to own at one of the Wyndham Myrtle Beach Resorts. That is the only way the owner would get Advanced Reservation Priority (ARP) access which is necessary to reserve the time you want.
That same owner would have probably paid at somewhere between $4.75 and $5.35 (estimated) per thousand points in fees just for usage in 2012. (That does not take into consideration what the owner paid in "Sunk Cost" when he or she purchase of the real estate was consummated.)
Based on Weekend usage an owner reserving a Friday night and a Saturday night would have to give up 41,500 of his points plus an extra 24,000 for Sunday night.
Using an estimated $5.15 as the cost of the 2011 maintenance and Fairshare Plus Fees, the owner would have to figure his minimum cost (not counting Sunk cost) at $337.33 and that does not include a Guest Fee if the owner has to pay that fee.
Given the demand for that time frame, the owner should, in my humble opinion, expect to get roughly $750 to $1,000 for the weekend.
I did a quick search on the Internet and found at least one rental offer for a FULL WEEK in early July where the owner was offering a 2-BR ocean VIEW as opposed to Ocean Front at Sea Watch for $1,600.
Keep in mind that at Sea Watch Plantation there are year-a-around owners who rent as well as Wyndham Points owners who rent. So your actual cost of a weekend in July or early August may be less or possible more
Good Luck