Hi guys en gals, I’m thinking of buying an Audi for my next car as I love the look of the A5, A6. Unfortunately I do not know allot about cars so I need some advice. My bugrt is €20,000 so second hand, need cruse control decent AC manual gear and smooth ride, 4 Door, and reliable ofcource. I don’t know if there is a performance difference in pertrol or desiol. Motorway driving a lot. Thank you in advance for you time and valued opinion. 

What can anybody tell you except their personal preferences,  prejudices and hearsay? My suggestion is that you read some professional reviews, then try a few cars for yourself, before making up your own mind.

Hello  ( Paul?), 

Wonder if you can do us a kindness and fill in your name on your Profile. 

I too think your best way forward initially is to look up all available on-line buyer’s guides. 
You will first need to decide whether you want to buy an A5 or an A6, and then decide whether you prefer diesel or petrol. 
Once you have done that, then it’s possible that owners of each on here will better know whether to respond or not. 
Since you don’t know a lot about cars, the all important advice you need to follow is -do not buy any car without having it professionally inspected before purchase. Yes, I know it will cost, but it will save you far, far more in ongoing costs and hassle if you don’t. Please don’t depend on ‘it’s got full service history’ claims, that won’t be sufficient. First spend a comparatively small amount of money out of your budget to better insure you are buying a good example. 
Kind regards,

Gareth.