Best way to spend 3.5k?

Hi. I am interested in a Octavia vrs. I am about to sell the 04 vw Passat estate ps140 that I have, turbo gone at 120k miles and looking for something a bit smaller and with better economy and perhaps not sooo low and wallowy in handling.

I have arrived here. Don't want an Audi, seem to pay for the name. Wondered about a Volvo and then ended up in an Octavia vrs albeit a newer one than I will afford and felt like the ride was tight and the throttle responsive. I see a plethora of these used as taxis/private cars so the fuel economy must be alright too.

Been having a look through the classifieds and not sure what to go for. Are there models to avoid. Is there common faults to check for. Is a newer model with high motorway mileage a better punt than a ten yr old low mileage. What would you buy with the budget. Cheers