Thanks everyone for the advice, still waiting on local quotes to re-felt though EPDM is looking most likely now as once the roof is cleared of all the old felt and nails, if I get someone to lift the roll up and centralise it, I can roll it to the middle, apply the glue, roll and brush out the air bubbles, turn around and repeat.
Once its laid and no air bubbles I can take my time sorting the edges and trimming battens.
Once its laid and no air bubbles I can take my time sorting the edges and trimming battens.