Rob when you get your quotes if you don't mind everyone putting in their ten cents worth you could post the particulars and ask the forum member :
- has anyone used them before and thus the quality of product
- to give you feedback on price vs. work quoted to be done
For example one way to get the cost down would to complete primary stage prep basically get it as good as you can and let them complete prep. Get them to spray it and take the car home with an 'out of the gun' finish so you can complete the final cut and polish (the labour intensive bit that could be completed over a couple of weekends depending on the finish you are striving for.
(I have used Gavin and his Dad at Paint Shop Pros a couple of times - his dad used to work for Rolls or Bentley I forget which but Gav sprays the cars most of the time I think and his out of the gun finish is highly impressive - almost no need to cut and polish!)