Looking at the pictures, no damage marker, the lack of service history and the missing key it’s very suspect
Unfortunately you only have 30 days from purchase to reject the car and this period has passed. You do however still have rights under consumer law to request the dealer to repair the car ( in your case the paint job) and within the first six months it is the seller that has to prove the paint defects were not present at the time of sale.
After being given one chance to repair the car if it is still unsatisfactory you can then at this point request a refund or a partial refund if you wish to keep the car. The dealer may also make a reasonable deduction for the use of the vehicle during your ownership.
I would also contact the finance company and inform them of the situation and if you paid the deposit by credit card your card provider as they are jointly liable for any purchase over £100.00.
Keep a record of all correspondence particularly telephone calls (if possible record them).
Be interesting to find out who the previous owner was as Burneston is indeed the Toyota factory just outside Derby.