First off, do you have health ins.? If you could use your ins. do you know what your ded. and co-pays are? Do you have a primary care Dr.?
If you go straight to a plastic surgeon you will have to pay 100% as it will be classified as elective surgery and health ins. doesn't pay for that.
If you have health ins. w/ a primary care Dr. , go see him and talk to him about your weight loss journey and show him your chest. Tell him it has been very pain full to the point that even just a t-shirt rubbing up against it is very irritating. Tell him it is very embarrassing to take your shirt off, that it has kept you from pursuing a relationship, and that an accomplishment you should be proud of is doing the exact opposite and you have gained weight back because you feel why bother when you look as bad or even worse with the weight loss.
Come up with as many depressing aspects of how your chest looks and you may get lucky and get ins. to pay for it. Those shows you see on TV like my 600lb. life not only get all there weight loss help paid for, like gastric by-pass, they get there skin removal paid for by there ins. Good luck !