As long as its smooth,clean and you open the paws so the paint can adhere you dont need to take it down to primer . 2pac primer is very easy to paint as long as you do every coat at least 10mins apart then you dont have to wet rub after each coat to open the paws. I would do 8 coats of 2pac primer and when your ready get the workshop to go over your work.
You will save a shit load of money, as long as you take your time and do the job right.
Look up youtube, ebay for cheap how to books, visit (dont ring) the places you want to take your car to and they will help you out.
It will take time but doing it yourself you will know your car alot better and have alot more pride in it
I would ring All Type Crash, they know what they are talking about and will give you very good options and alot of help