i am based in midcornwall,  and to be honest there is a lot of comp,  be it summer brigade working for beer money around newquay,  established wc who are cheap as there out goings are cheap,  i lost work to a wc who charges £5 per 3 bed house,  he then lost these to 2 trad guy charging £4,  the one thing i notice more in cornwall than any where is wc working out if there cars
i make a living at it, but i treat it like a part time job, as i dont need that much to live on now,  i dont know what plymouth is like, but from the work i have done there, there seems to be loads of wc 
the last 2 rounds i seen for sale in cornwall was  1500 went for 3000  and 150 went for 200,  there is not great prics for the work down here,  more of a numbers game down here