Lexus is a upgraded Toyota. Lex/Toy were practically indestructible up to the early 2010's. Older Nissan Maximas have the same bullet proof reputation no later than 97. these cars are fairly easy to work on, parts are available and they have a cult following.
You're going to pay an arm and a leg for an alternator or starter, like 200 dollars, but they last well over 100K miles so once you replace it you're not going to need to. Water pumps are a pain in the ass. it just takes time and you HAVE to take off all the parts to get to them. There is no "short cut," of well maybe I could wiggle it past the radiator etc., drain it, take your time and do it.
Fixing your own car is something every male should do, sadly with the effemination of men, most can barely put gas in their vehicle. And to be honest the engineers which design modern cars (looking right at you
@Maysam talk to them unfuck this bullshit) it seems the manufacturers make servicing your own car exceptionally difficult on purpose so the owner HAS to take the car into the dealership for service. Fuck my cabin filter is a four hour job @ $60 buck an hour to replace a $15 dollar filter. I put it off for as long as I could but after the cabin started to smell like fresh summertime ass sweat, i changed it myself, and invented some new curse phrases while doing so.
It will also help you build confidence, take your time and don't get discouraged, you have YouTube instructional videos. Too easy. Back in the day when I was starting to bust my knuckles on cars, you'll understand this when you start working on your Lexus, all i had was a Chilton's mechanic's manual.
Lastly, DO NOT do anything that involves a suspension spring compressor. Those things are called widow makers for a reason. One horror story was one guy had removed a front truck spring and while it was compressed, he DROPPED IT, and the thing slipped out of the compressors, and took his face off.
When looking at this car, inspect the shock towers in the front, under the hood and in the trunk, if they show any signs of rust, PASS on it. Pay a little more for a car that is structurally sound. Because unless you really love the car, it's going to be a money pit. Plus, you should enjoy driving your first car as well. That's the goal.
Good luck.