I think personally by limiting it to £28K you are cutting yourself short and missing out on other cars. For reference I had two budget reviews (the first was fairly minor, the second was a different kettle of fish, but I ended up buying the dealership's brand manager's car).
It really is (as said above) worth looking within the BMW network and you may come across something which meets your requirements. I would also add you will save some money potentially as all AUC cars have a 12 month warranty
, and whilst as not as comprehensive as a manufacturers one it is very similar to the extended ones at comprehensive level - bar the clutch facing.
"*The following are not covered by the BMW Approved Used Car Warranty: brake and clutch facings, discs and drums, bulbs (except Xenon), fuses, channels and guides, weather strips and seals, handles, hinges and check straps, trim upholstery and cosmetic finishes, wheels and tyres, wiper blades and arms, glass, auxiliary drive belts, coolant and fuel hoses, the cleaning and adjustment of any component and all service items or items that will require periodic replacement. Corrosion is also not covered by the warranty."
Furthermore, it also means you reduce the level of risk involved (I find the whole arrangement of you paying him or calling them direct over the finance highly risky).
The mineral white car needs minimum £300 spent on it (roughly speaking) to do the front pads, that is before anything else. Over the service pack you have not confirmed when the last service was or is due, if you are not careful then you will loose any opportunity to take advantage of the remaining period (of course some of that is also related to your expected mileage).
A further point you say the warranty on it ends in May, is the seller paying monthly or annually?
If the seller is paying monthly the mondial warranty
cannot be transferred to a subsequent owner. If it is annual it can, when he says it ends in May it does point to an annual policy though.
If it is not, you could therefore be finding that you are paying out for the warranty far sooner than you expect.
The reason for the monthly one not transferring is it is a rolling policy where you just keep paying until you decide you do not need it.
Over the blue car, hmm, not bad not sure on the interior, but that is a personal choice. It looks fairly good and still has some manufacturers warranty left (albeit only until next month).
Edit:
Just had a look at the local AUC cars around £30-£32K, some with around 20K as opposed to 41K on the clock and a little bit younger. The £32K cars were late 2013/early 2014.
I do not want to sound harsh or mean in anyway, but I feel you are just not considering the overall picture of the car's costs, before you know it you could have spent nearly as much as an AUC one. This is one of the reasons linking back to my first statement about the second budget increase I went through as one of the late 2014 cars I looked at in good detail with only 20K on the clock was not far from new tyres being needed on the front (they still met the AUC requirements mind of 3mm) and a few other bits and when it really boiled down to it the car I have was a year younger with only 2K on the clock (he recently just glided through 5K on the clock incidentally!).