I really don't think there is much you can do. This may be incorrect but I heard that if you lose the weight more slowly, there are fewer problems with excess skin. (Somebody correct me if I'm wrong.)
Please don't use this as an excuse not to lose weight, however. I've taken the slow approach to losing weight and have seen a little excess skin in spots. This doesn't deter me from continuing to work to lose more weight.
FWIW, I have read about cases where people who have had excessive weight loss that got their health insurance to pay for skin removal. However, in those cases, the excess skin was posing health issues (bacteria growing in the skin folds). Otherwise, you're correct---in most cases having such surgery is an out-of-pocket expense.