Hey there, everyone. I'm relatively new to cycling and just picked up a bike off of craigslist for the sole purpose of recreational riding/short 5-10 mile commutes. I found this for $75, which after doing a little research seemed like a decent price that I should jump on. Is this bike worth the effort of investing a little money into? I was thinking a rear rack, definitely a new saddle and fenders and a rear blinker. I'm about 5'10 and weigh 135 give or take. I'm a pretty limber guy. I would some output on you guys with a little experience. Was this a score, or a mistake?

Picture of the bike is attached. Thanks!