kenaiqueen wrote: However she is offered without body sanding for about $100 less than with. (Both ways are available.) How important is this?
It's an appearance thing. This is totally up to you. This is for sanding off any parting lines, those little ridges that can form where the two halves of the mold were together. A good sanding job can make these areas nearly invisible.
And how hard to do it yourself if I don't get it with the sanding?
It's not terribly hard to do, it's just tedious. In order to match the smoothness of the rest of the part's finish and make the area you're working appear exactly the same as the rest of the part, you might have to go through numerous grits of sandpaper, starting with something in the low hundreds and working all the way up to wet sanding with something in the low thousands, with a few intermediate steps in between. This can be very time consuming work. Obviously you don't want to have any body blushing done before this step (if you're going that route).
Would I have to seal the body afterwards?
No, you shouldn't have to. The resin should be fairly homogeneous through out. Resin sometimes appears to have a skin because when it breaks, the sections of the break can have a grainy appearance and texture as compared to the finished outer skin. This is just a product of the smoothness of the mold and how resin fractures not any actual resin "skin".
Also, the shipping is listed at $99. Yikes to say the least, but I realize she is a big girl. Is that a good price?
Resin is heavy. If you want to check this price go to the UPS or FedEx site and get a quote. You'll need to know the weight of the doll (add a couple of pounds for packaging) and the approximate dimensions of the box. And of course the address she's being shipped from.
I should mention that I have never sanded parting lines on a doll, however I have done the same process to a number of resin garage kits in my modeling days. The process is the same.