You have a similar agreement to what I have, but let me tell you straight off the bat that the interest is waaaay too high. I am paying around 5% APR on mine.
I think my figures were:
purchase price £48K
deposit around £19k
36 month agreement at 406gbp per month
I opted for lower ballon of around £18.5k (but was offered up to 23k afair).
If you want I can see whether my asset finance guys are taking on more business because 11%+ is taking the piss unless you have a bad credit rating?