My facial hair grows like a mother fucker, and I've had electric razors in the past. Used shitty BIC razors, braun electric, some 6 blade cartridge razor, and have used a double edge Merkur safety razor for a year now and won't ever be going back to an electric. The electric razors tug your hair too much for my liking, and when it comes to closeness the single blade disposable razors seemed to perform almost equally.
Using the double edge Merkur razor i pretty much never get ingrown hairs (which didn't happen often, but would sometimes occur under the chin) and it will give you zero irritation if you do it right. It's a sharp as fuck blade that will slice your face if you apply pressure, but if you just hold it the right way and let it slide down your face at the right angle, you'll get the closest damn shave and it's much cheaper than any other alternative I know of.
For the razor you're looking at maybe 30 bucks, a 100 pack of blades cost me 7 bucks on amazon (I use 1 or 2 blades a week, shaving roughly every other day), and soap and a brush shouldn't be more than another 20 bucks.
I'm pretty damn picky when it comes to a good shave, and that is the most fool proof and cost efficient way to shave in my opinion. Cheap, close, no irritation, and no having to buy cartridges or batteries. Just my 2 cents.