Draw PDF Architectural Plans into Autocad DWG Format

Hello all, I'd be interested to know the cost to draft up the attached pdf architectural plans into Autocad format, so I can use them for a new project proposed at the site. I currently use somebody for this service, although am thinking of making a change as he is proving unreliable and slow, so I would really appreciate an indication as to costs for this project and fees in general for this type of work. If the figures work out for me I will be employing somebody in the very near future, I would envisage I'd provide at least one drawing-up project of this size and nature every fortnight, possibly more. Many thanks, Rob Humphreys.