as i own a 735iA ( built `96) i can`t give you any further information about maintenance and repair costs of a 728i model. I just wanted to drop a line about the Europlus and some things that are very important for you if you buy the 728 as mentioned in your message.
When i bought mine like 4 weeks ago, the dealer said that they assure to deliver a fully functional car, with new service done and new TÜV.
They changed catalysator,MID ( multifunctional display ) , did some paintjob as one mirror had a small scratch and so on. I also got brandnew tires and they also changed the wheels cause i didnt liked the ones mounted very much. ( unfortunately i didnt got the 18 inch
)
I
highly recommend that you buy the 7 series at a trustworthy BMW dealer with ( hope for you you`ll get it ) 2 years of Europlus warranty. Maybe this will raise the price of the car but its definetly worth it .
Good luck and enjoy your new ride ...
PS: if youre a Porsche driver atm, the better buy would be a 740i...
Greets Paddy