Just wanted to post that I've been cutting my own hair since I was ~16 and my parents told me I had to pay for that sort of thing myself.
I'm a white guy with short, straight hair and the idea of paying $8 +tip at the local Supercuts or Great Clips or wherever for a 5 min. trim for the rest of my life really bothered me. (just one of the early things that put me on a similarish path to FIRE as MMM around the same age/time). Don't even know what cuts cost now.
Saw an infomercial for the Flobee and decided to try it. It was $60 at the time, and like $15 or $20 for their tiny vacuum cleaner they make to go with it. It was made REALLY well. Heavy duty -at least back then. But I think it appears to be the exact same design for like ~30 years now. Still works perfectly. Replaced the vacuum once, but that thing's tiny and super powerful. It's got a physical 'kick' when the motor turns on, so it'll pull hair up nice and even.
You can buy replacement filters for it, but I just clear out most of the hair each time and reuse the same filter forever.
Technically, you can use any vacuum, but I'd strongly rec. you consider getting the vac to use just for hair. You don't want to ruin an expensive vac that's not meant for handling that much tiny bits of hair.
It's kinda hard to cut the back myself (I use a mirror and good coordination). i wish my wife would do it, but she never tried. It's fine. Takes me like 5min. for each cut whenever I want and just as long to pull everything out and put it all back away.
It's been a small investment, but fantastic return.
It may sound and look stupid, but it works just like how at the hairdressers they comb sheets of hair up between their fingers and clip it across the top edge. Watch the videos of it. If it looks like it'll work for you, it will.
Sorry, I won't put a pic up of me. But I'm an author with my pic on Amazon and think my hair looks decent enough. At least how it always looked from someone else doing it.