I have a Mk3 Mondeo TDCi and it’s VERY spacious. I can get three bikes in the boot and 4 people (if carefully packed). I had a look at an SMax and wasnt convinced it was much bigger in capacity than the Mondeo (talking about useable space as I know the S max is taller internally).
as far as repairs go, I do all my own servicing and I have just replaced the suspension strut (weak point on earlier mondeos) and so far haven’t had anything major go wrong at 82k! but cars are as fickle as bikes!
For tyres, I only ever put Part worn tyres on from a reputable source and they are at least half the price (155/60/r17 IIRC). I dont think you need to have the high speed tyres as we all can legally only drive up to 70mph in the UK!