BMW 3 series estate or Audi A4 Estate help me choose

[sarkin]

As per title looking at BM 3 series or Audi A4 estate 2l, 4/5 year old 35-45,000 miles on the clock. we are a family of 4, wife 2 kids, 5 and 8, driving 10,000 miles a year. Car is for my wife to drive to work and shovelling our $hit to and from the various activities we do at the weekend. I walk to work as live near my office.

so do we go diesel or petrol

automatic or manual

3 series or A4

what do I need to look out for regarding any potetial problems.

thanks in advance