There is something not right about that deal, if you have a business that is either making loads of money, or is making loads of cash, then you would not be selling it for peanuts.

with ref to the partnership, avoid it at all costs, remember, there are no friends in business, cut him out and go for it yourself if you so wish.

Would you really want to own your own motor trade business in this day and age? I certainly would not.
What are the advantages? what is the long term? where do you want to take the company?

There are no grandfather rights in the MOT system anymore, you will have to re-apply. Though there are some dispensatons.

Being your own boss sounds great, but the trade off's can be hard hard work.
think about the hours you are going to have to put in, 40/50/60/70 hours a week for how long?
Working on cars for the rest of your life? is that what you want, no paid holidays, no sick pay, can you afford to run it if you injure yourself?

Not trying to put a damper on it, but pound on pound return, the motor trade is a poor place for your money.