Hi, I know this is a dated posting, But I'll reply anyway. It may shed some light.
If you are planning to have SRS, Then here are a few things to consider. Usually there are a few methods for lining the new neo vagina. One of them is using the penile inversion with scrotal sack, which has alot more elasticity vs. a penile inversion with skin graft which is the other option. There is also the third option, where they use a segment of your colon. The scrotal graft, is cheaper than the skin graft, and, finally the most expensive of the 3 is the colon segment. If you're planning on SRS, I would not do it. The more options you have, that's one more financial option for you.
P.S. The scrotal sack will experience alot of shrinkage without the testies, giving the doctor less scrotal skin to work with, Meaning you'll most likely have to pay a higher price for the skin graft or colon segment options.