If you put down a decent deposit, you can get a good rate on HP agreement with Seat Finance. Just make sure the dealer your using uses Seat Finance as some use others as well.
I think mine is 6%
If your going for
PCP i think the lowest rate is 8% over 3 years but if you refinance at the end of the
PCP term with Seat it might be as high as 10%
Might be worth seeing what rate your bank can give you.