stretch marks and loose skin happens when you lose a lot of weight quickly, i did it 6 years ago and i thought it will fade away by time but it didn't, i saw some people talking about applying topical Vitamin A and E on the skin helps to reduce the stretch marks but i never tried it, i think muscle building is good when trying to lose and maintining weight and also it will look better if you gain muscle after getting the loose skin, so peat ideas are helpful here.I bought Palmer's cocoa butter product for stretch marks. It's too early for results, but I get a nice warm feeling when I put it on. A nice vibe I didn't have when using other creams for my dry hands, most of which actually irritated my skin when applied.
but anyway you can try applying a mix of cacao butter, olive oil and coconut oil daily on the stretch marks areas and see what happens in period of months and report back.