Note that FFL01 licenses are not issued to those who just want to do this as a hobby.
Assuming your location is zoned for business, you will have to get your business license sales tax ID number, etc. before any FFL01 will be issued.
There are also some other requirements related to the business inventory having to be locked up separately from your personal firearms but it's been a while since I looked into it.
As far as 'angles' for making money as a dealer, it seems that buying used firearms or whole collections from widows or people getting out of the hobby and then re-selling is HUGE for the local shops around here. They pay 40%-50% retail(or less) and then make a killing. Most widows/family members are faced with unexpected expenses and just want to unload whole collections with as little hassle as possible. Often they have no idea or interest in any of the critical details of the weapons. I've been at these shops and have witnessed the situtation and it's very depressing - for the family members. Very profitable for the dealer.
I was interested in dealing military and military 'style' firearms because that's what interests me.
Most shops have a variety of firearms to appeal to more people.
Home defense and conceal carry is very popular lately and seems like a good segment. Lot's of competition, though, with lots of dealers selling online.
I believe the BATFE audits anything other than an 03FFL to make sure they are actually acting as a business. If you aren't going to buy/sell regularly they don't renew your license.
With that said I do know a guy who runs a 01FFL business out of his house.
I have an 03FFL which allows me to buy "Curios and Relics" as a "collector".
Also, might be worth checking out to see what some distributors programs are for private ffl. Distributor like galleryofguns/davidsons have private ffl listed when people do searches, I don't know how much of a cut/commission it would be, but when I searched for firearms on galleryofguns, a private ffl was listed the cheapest price in my area for me among some other shops that were much higher. They keep all the inventory until someone orders through their website and choose the ffl they want to go through.