I would charge £100 for the outside and £75 for the insides, or £150 for both.
I am not the cheapest! The roof will take a while, do not pressure wash it as the seals will probably leak!! As you are not wfp i would use a hosepipe and brush to get the worst off and then rinse. As for the rest of the pvc you can pick up pvc cleaner in most shops. Pressure wash the frames and windows to save a bit of time.