We managed to get £500 of the AP of our BMW 1 series in 2020, this was done through Stratstone BMW, it was as simple as contacting Stratstone and mentioning that other BMW/ Mini dealers where offering a dealer discount of between £250-£500 off.
I am currently trying to contact Stratstone to see if they will provide another discount on the AP for 218 GC which I must say it’s AP is extremely high. With Motability providing their £750 and if Stratstone offered the £500 it would be worthwhile even though a lot more then it was 3 years back.