Cynic that I am, I have some doubts about the story of the 88 year old man. It would not be the first time when somebody made up a story and cashed in on a go-fund-me type of account.
First, he has been and is now collecting social security, perhaps not enough but something. Medicare coverage begins at age 65; not the best health insurance around but it's now only about $185/month and is fairly good at that price (although the premium has gone up and will probably continue to do so). Also, the best that a bill collector can do is place a lien against your house; the only entities that can take your house are the mortgage company for non-payment and the property tax collector. It is possible, though, that taxes and insurance forced him to sell.
So the details we have been given, IMHO, don't add up. Do I feel for him? Yes. But is it possible this is, at least partly, a scam? Yes.
Do you know that Go Fund Me keeps 10% of all donations? I knew someone who was diagnosed with cancer, no insurance. A GFM account was set up and I was going to send $500. Until I read the fine print that said they will keep $50 of that $500. I walked to his house and handed him the $500. (This was 7 years ago; maybe that has changed since then.)