thanksI would finance the full 200k putting the minimum deposit (say 10%), this will get you the best possible rate.
Then (as was already said) phone up the vehicle finance company and do a capital reduction of 130K (150K-200K*10%), this will probably leave you owing more than 50K but you'll be paying that back at the original 200K interest rate.
I would then try and save a bit each month (1k-2k) and then pay it off when your savings = the settlement amount. That should take about 2-3 years.
Also very NB in this scenario do not take top-up cover from the finance company/insurance company. You don't need it as you final amount owing to the bank will be rather small (50k-60k)
that seems like a plan