Funny you should say that.
I have just had my contract cancelled because I am too old ( 60 ) and my vehicle is too small ( 1.5 ton) to deliver wine to resturants any more.
The weird thing is they have been using 2 guys 1/2 my age with even smaller vans to do the same work at 70% greater cost.
Can't figure out how this works out which is probably why I never went into management.
Having been a contractor / sub contractor for the last 40 years dealing with the authorities it is not the problem many make out.
Ask nicely act like an idiot ( helps if you get it wrong ) don't argue and you rarely have a problem all the pencil d..cks just like to feel they are important & powerful.
The biggest problem you will have & the one I have, which is why I am here as well, is finding out the "secret information" the manufactures hide from you unless you have a 10,000' shop with 25 car parking spaces & agree to hold $ 500,000 of their stock on the floor in the vane hope some one might happen to come in & buy something . The idea that any one can make any sort of a living by actually fixing their machines properly when all they really want you to do is tell the customer it in an uneconomic repair & sell them something new is abhorrent to most companies.
Hang in there, take pride in your work and be prepared to run at a reasonable loss for the first year or two.
I have people driving 40 miles to me now because I will at least try to fix their equipment, don't charge $ 50 quote fee before I even book a job in & give honest opinions even when it is not in my favour.
People appreciate being treated like a human being and not just a wallet on two legs.
And one thing I have learned years ago, never answer your phone while you are with a customer, just let it ring out and get back to them latter.
Even if the customer you are dealing with tells you to answer the phone the reply is "the customer I am with is the most important one in the shop, I will call them back after you are gone"
this does 2 important things.
1) it tells them you really do appreciate & value their custom.
2) If they can not get you on the phone they will know why. Just make sure you call back.