Newbie - What Should I Buy?

[Siy]

Hello everybody... a newbie here in the UK.

I am venturing into audi ownership for the first time. I drive a BMW M5 (but willing to leave the dark side!)

At the moment, my wife is expecting our second child, and hence needs to change her car for something bigger.

She wants an estate, and we have always liked audi's.

I don't want it to be underpowered.... and like toys onboard - as many as possible.

Budget is only about £12k

looking for advice on what we should look for ...A4/A6 (many differences??? - clearly an audi novice!)

Would want to get something with mileage below 60,000 miles.

Am I expecting too much - what do you guys think I could get?

Thanks all in advance

Siy