Honestly you need to be careful with those newer Acuras long-term reliability isn't their forte. The engines have cylinder deactivation I believe a timing belt but luckily for you the transmission is a 6 speed automatic not the problematic 9 speed.

Under 100k miles or so it could be a great car but we don't after that.

Those are great SUVs. Make sure you have a trusted mechanic perform a pre-purchase inspection before you give the seller any money. The only downside to those RDXs are they still use a rubber timing belt, so if you keep the car a while you will have to change it at around 90K miles or so. Other than that, they are excellent and also pretty fun to drive for an SUV.

See here:

https://carkiller.com/scottykilmer/qa/2013-lexus-rx-350-or-2018-acura-rdx/#post-36458

Also, keep in mind that generation RDX comes with the 3.5L V6 (J35Z2) which has cylinder deactivation (susceptible to engine wear/damage and oil consumption over time) - even if you disable via aftermarket (through software) the hardware is still intact.  At least that engine is port injection, so you don’t have to worry about carbon buildup on the intake valves.