I buzzed my own hair for 3-4 years. I went with a 4 for most of that time. I must have saved almost $1,000 on haircuts and loved how it was low maintenance, but eventually I decided I look better with a barber doing an inch on top and tapering to a half inch in the back. But I'm about to get the clippers back out because I have no idea when he'll be allowed to reopen his shop.
I'd agree with the buzz cut recommendation. Start with an 8, see how you like it, but don't be afraid to go shorter. The hard part is shaping the back. Get a handheld mirror, work in small strokes, and be patient.