I'm so sorry for not coming back sooner - thank you so much for all the concern and interest. I wanted to wait until I could tell you all something definite before posting again.
So the pub last week was good but not quite in the way I expected! Dd and cb hit it off straight away - they've not really seen much of each other before apart from the previous drinking session 
a few Fridays ago. He's more her age than mine, and she is of course very beautiful (Biased? Me?). Cg and I were looking on like proud parents, and I suddenly realised that while, without a doubt, I think cb is knee tremblingly good looking, I couldn't actually envisage anything happening. After a couple of drinks, encouraged by the parents, cb and dd left us and went off on their own to a night on the town.
Meanwhile - cg and I talked nonsense, avoided anything too close to the bone, drank more, laughed - and somehow suddenly the subject of "us" came up. Aided by several giins/beers, cg told me he'd been interested from early on, had confessed interest to cb, and had tried to bide his time. But now that we were half way to being friends, not just builder and customer, he wanted to know what I thought. We had a bit of a discussion in which I explained I was wary of mixing business and pleasure, and said that I had in no way been anticipating anything like this. He said that was fine and to think about it for as long as I liked.
I've thought about it. We're giving it a go!
Dd reported back after her date with cb that he was a nice lad but with an awful lot of issues, and that she'd be a fool to get involved! She did elaborate but it doesn't feel right to repeat anything here. Naturally, since my crush on him has abated, I'm now able to talk non stop to him and to flirt like there's no tomorrow. He continues to make me tea and, even knowing what I now know, nobody will convince me he's not a very nice man!
I will keep you all posted on what happens with cg and the extension! Thank you so much for making this fun and for keeping me (nearly) sane. I'd do some xxxx's if it was allowed ...