I just found this post while searching for it.. my Rabbi mentioned The Chesed Fund yesterday at shul, and that his "great nephews" are benefiting tremendously from the kindness of so many people! Apparently these are the boys he was talking about, and they have raised over $70k..
https://thechesedfund.com/cause/help-modify-a-home-for-handicapped-twins-eli-and-nachi Amazing!
Looking at the campaigns, it looks like there are a lot of worthy causes coming together on there. As OP said, it seems the only cost is the credit card fees. GoFundMe will charge 5%.. imagine raising $70k on GoFundMe and finding out $3,500 has to go back to them?
I had a friend try to raise money for a trip to Israel awhile back, and he was searching for a website that wouldn't charge out the nose. He ended up using gofundme. Found that most places try to double dip on charging the donors when they pay, and the recipient when they receive! Scams. I wish he knew about this chesed fund. It seems like you're just throwing money away by going on any other website.