Unless the excess skin creates medical problems - rash, sores, etc., - insurance is unlikely to cover plastic surgery. The cost will depend on what you need done and maybe where you live.
Several plastic surgeons usually attend OH conferences, and they'll do consults for free, so I signed up for one at the last conference I attended, about a year ago. The surgeon practices in Beverly Hills. He told me I would need a LBL (lower body lift, a removal of a wide band of skin all the way around, usually at the bikini line, which takes care of the abdomen, muffin top, back drapes, and he told me it would "probably" take care of my thighs as well) and arms/breast reduction. So two procedures all-in, each costing $18K. They would need to be done at different times, for safety. Total $36K. Yeah, no thanks. I have the $$ but have better uses for it.
Take a look at the plastics forum, lots of good info there.
My insurance is covering a pannielectomy and I am having a "tummy tuck" done at the same time. This will take care of my front and probably cost me about 8k out of pocket. Also have plans for 3 more procedures in the future. All self pay and probably 30k out of pocket. I lost over 300lbs and now I want to look good. I already hit the gym hard and plan to hit it even harder once I am healed.
A good ballpark estimate is $35,000. The cost of a mid-range car. The car will rust out and wear out, you will have the improved body for life. Many people do a second mortgage or take a loan from their 401K to finance it.
Real life begins where your comfort zone ends
I had a fleur-de-lise abdominoplasty last year. Costs can vary greatly from area to area. I'm in Massachusetts, and medical care is expensive here. The first estimate was 15K, but I shopped around and was able to get it done for 7K. I could probably use two more procedures to remove skin from my arms and my inner thighs, but the stomach was the biggest part and I am so glad I got it done. It was worth the cost.
best of luck,
Surgery May 1, 2013. Starting Weight 385, Surgery Weight 333, Current Weight 160. At GOAL!
Weight loss Pre-op 1-20 2-17 3-15 Post-op 1-20 2-18 3-15 4-14 5-16 6-11 7-12 8-8
9-11 10-7 11-7 12-7 13-8 14-6 15-3 16-7 17-3 18-3
I'm having a lower body lift, arm lift, and small breast lift all done at once for about $25k (that' the surgeon and hospital fees) out of pocket since my insurance won't cover any of it. And that's in the DC area, which also isn't that cheap. So it also depends on if you can combine things to minimize multiple hospital stays, etc.