Is there any research funding for Independent researchers to work staying at home?
I don't know which country you are in, but in the United States at least, a lot of grants assume you will be affiliated with a university or other institution (which is why there are things like indirect costs) and are not set up to be given to individuals with no affiliation.

That said, if someone has a decent scientific track record (eg. you're not a risk to the reputation of the university) it is fairly low-risk for a university to offer you some sort of 100% soft-money position (part-time research professor, etc.). Soft money means your entire paycheck has to be covered by grants, so the university doesn't risk any money on you themselves, they just give you a university affiliation so you can go hunt for grants. If you had a soft money position, and were able to get grants, you are pretty much your own boss and able to decide whether you want to come in to the office or work from home.