Most of them are not going to be allowed to open your mail or handle your checks. I use iPostal and they only scan a picture of the outside of the envelope so you can see who it’s from and decide if you want them to forward it or trash it, they don’t open the letter. Each individual piece of mail can be forwarded to any address you choose, you can have them send it to yourself or to friends. It costs $0 if you opt to have them trash junk mail but it’s usually $2 to have a letter forwarded domestically, more for a package or express shipping. And I think the whole service is like $9 a month.

If you go with iPostal though be careful about the fake address you choose. For instance if you are going to get an iPostal in Baltimore, it might give you two or three Baltimore addresses to choose from (it’s usually like a Staples location). One of them will be eligible for both domestic and international shipping, one of them might only offer domestic. It sounds like you need to pick whichever one does International too

I looked into the Long Stay Visa in France exhaustively when I had a remote job with an American employer. I read blog posts online from other people who had done it, I spoke to a lawyer who said it was possible, etc. I asked Reddit about it and people attacked me, yelling at me for trying to be an evil digital nomad who breaks the rules of the country I’m interested in; the reaction was ferocious. They said the stipulation that you can’t have a FRENCH job also means you can’t have any job whatsoever. It made me think I was not getting correct information elsewhere so I panicked and gave up. A few weeks ago, a friend of mine with a remote job successfully got the Long Stay Visa. So apparently it actually IS doable.