I agree about using your own car, you can't take it with you and no offence, a 3.7 on LPG won't set the typical cherished classic market alight in years to come, so I'd just do that, it's a great place to whittle away the hours.
If you do a cost comparison, additional fuel on the 8 vs Buying a car, tax, mot, insurance, etc and see where it all falls.
The other thing is, the 8 is the devil you know, how risky would it be to start a new job and have the new car leave you on the side of the road because a previous owner skimped on something?
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