OTD.
How many miles are expected out of those RX350s?
We see them in the shop on the regular for maintenance with 150k+ on the clock. Couple of things -- Lexus dealers RARELY see a transmission go bad. In terms of the RX's, the things that you need to look out for are this -- some of them have oil cooler pipes that are rubber; the redesigned ones are metal. The rubber dry rots and wears out, and can potentially leak engine oil and cause the engine to seize. There's very few of these out there, there was a service campaign to replace these free of charge for awhile there. If it hasn't been done, and it's a car that's in your price range, it's about 2 hours labor to replace the lines. If the car has oil cooler lines, you can look above the filter housing, the lines are mounted right above the filter cap. Also, the rear shocks do leak from time to time, it's about 1.5 hours to replace them, and the OE Lexus shocks are $55 a piece. Water pumps do leak at some point; the bearing in the pump itself usually wears out, and it gets incredibly noisy; you can do this one yourself if you're handy and have some basic hand tools such as a few ratchets, a floor jack, and some patience. Otherwise, it's 6ish hours to replace it. Tires are hit or miss -- if you prefer a quiet ride, Michelins, if you prefer long tread life and don't mind slightly more road noise, Goodyear Assurances. Brakes typically are done every 60k or so; if you go aftermarket, they will squeal a little bit. You typically can machine the Lexus/Toyota rotors at least once to save some money if they aren't too rusted on both sides.
I've only put a transmission in one Lexus, and that was an LS460L that the owner beat the dogshyt out of trying to race AMG S-Classes and BMW 5 series V8's.
Random aside: I think I remember seeing a 2015 RX350 with 74k on the odometer that was just traded in after the last owner had it for 18 days; his wife was complaining that the car was too big for her (she had an ES350 before). I think I heard them saying that car was going to be in the 20's to get rid of it, much like that '14 ES350 that's got 57k on the clock.
