I think there are limits on what can be charged but I'm not sure what the per point price is. But for example, if the person is going during a time that typically has discounts, you are not likely to get more than the discounted rate of a woods room at WL for a night at VWL studio - or the discounted rate of a standard room at BC or BW for a night at BCV or BWV studio. In fact, you will have to discount some more to compensate for the restrictive cancellation policies. 1 and 2 bedrooms are harder to calculate because they are not discounted very often for cash stays and the hotels don't have compariable rooms.
Using the AP discounted rate listed on Mousesavers for Jan 2005, it comes out to $140/night with tax for a WL woods view. If you multiple this by 7 and then divide by 104 (number of points to stay in a studio a week in Adventure season), you get $9.42. So $10 a point is not unreasonable in this case.
The Feb-April AP discounted rate for WL woods view is $190. The points for a week are 134 in Magic season. This works out to $9.92. So again $10 a point is not unreasonable.
Looking at rate rates, it comes out to $17.26 in value season and and $18.35 in peak season. You will need to discount off this to compensate for booking restrictions plus
AAA discounts are pretty easy to get - say a 25% discount - about $13.50. When the deep room discounts that Disney is giving dry up, I can see the points coming up to about this amount.
Now, BW and BC discounted rooms are not as cheap so you could possibly justify a higher price. Mousesavers does not list an example for the value season, but it works out to about $300/night for the spring. The point cost is the same at BC/BW, so it comes out to $15.67. Using rack rates and a 25% discount, I get $17 a point. So maybe those resorts should be going for more, but given you can book with any points after 7 months, I doubt you can ask much more.
I did one other calculation - going off the rack rates of a studio itself. Since I think Disney's prices are overpriced for DVC rooms, I'm going to make the discount 40%. This comes to about $13.50 again for VWL and only slightly more for BC/BW. For a 2 bedroom, $13.50 works out to about a 25% discount.
So bottom line, until Disney's room discounts dry up, I figure points will go for $10. When they do, I figure the point price can rise to about $13.50.