hi Guys this is my first post,
this question might have been asked before but I was not able to find it.

I am planning to buy a AUDI A4. Actually either a bmw 3 series or mercedes c class or Audi.
I want an all wheel drive cos of the snow here but i can settle for rwd

so coming from a Camry car, my questions are:
I am planning to buy a used Audi 2009 onwards
with less then 70k miles on it.

compare to camry what should I be expecting repair wise for audi compare to bmw and mercedes.

roughly how much per year.
also can i get an extended warranty on it even if its used (do i even need extended warranty)


any other particular thing I should be aware of ?
Any specific year model I should avoid.
I will appreciate all the answers, feedback

thanks alot