hi, yes your right not to have paid him, that's just taking the ... mick
he should have told you what needed doing and then quoted you a price before doing any work
and for collecting some moss off your roof, that doesn't exactly solve what ever issue you may have
he may scraped it out of...
hi you may have already checked this but it may be a leak on the lead flashing above your bay window or even a cracked roof tile, I know you said it didn't get wet when it rained, but it could take a while for the water to build up above the ceiling especially if there's insulation up there. or...