you can use a multitool on any PC/keypad and skip hacking, and it "only" costs 120 thingies to craft a multitool. I savescum liberally on it all though, basically save right before a hack, abort if the timer counts down, try again, and reload if I burn all my tries. 90% of computers have useless information on them anyways, so I reload my save if I used a multitool on it. I don't think there is any achievement for hacking every PC/keypad.
and yeah save games are exactly where you save, on ps4 you can only "hold" 11 save games I assume its similar on PC. Saving is SUPER fast, like 1-2 seconds, but reloading a save is slow like 20-30 seconds.
man I can't wait to get to hamplanet i wanna sex her up. If you take a shower in Adam's apartment he gets naked but you never see if he has a regular dick or a robot dick