Is it the previous generation rav? (2012-3019) if so you'll be going from one of the most reliable cars on the market to one that'll most likely need more investment from you. I'm not trying to put you off or scare you, I just want you to be fully informed.
I see the one you've been looking at has ended on eBay.
The 3.0tdi suffers with swirl flap issues, timing chain issues, injector issues and sunroof issues on some cars. Budget 1k-1.2k for timing chain replacement and £600 I think for swirl flap repair and £600 odd for injectors. Besides that 3.0tdi is generally reliable. It doesn't say full service history which would be a worry for me. At the Mileage you're looking at I'd expect to see documented gearbox oil change.
Also make sure tyre wear is even on tyres on the same axle and they should be the same brands as uneven tyre wear can damage the quattro system.