You won't get more than 10-11% on an A3.
Fair enough. But then why get the A3 when the A4 costs the same due to the much bigger discount?
Audi A3 Sportback 2.0 TDI 184PS Diesel, S line Manual 5dr - £25,087
Audi A4 Avant 2.0 TDI 177PS Diesel, S line Manual 5dr - £25,658
Well, okay, not the same, £571 more. Pretty sure the residual value would be that much better on the A4 anyway though. Plus, I guess the A3 has the newer 184 BHP engine.
Then again, you may want petrol, and a saloon. But what horrible petrol engine choices you have now...
Audi A3 Saloon 1.8 TFSI 180PS Petrol, S line Manual 4dr - £25,580
Audi A4 Saloon 1.8 TFSI 170PS Petrol, S line Manual 4dr - £22,575
So £3,005 CHEAPER with an A4 saloon over an A3 saloon. Might as well go for a Black Edition then?
Audi A4 Saloon 1.8 TFSI 170PS Petrol, Blk Ed Plus Manual 4dr - £23,860
And still pocket £1720 for having the bigger, higher spec car.
In fact, why have an A3 at all when you can have a 328i M-Sport for that money...
BMW 3-Series 328i M Sport 2.0 Petrol Manual 4dr Saloon - £25,904 (well, an extra £424)