Tough one mate. If she insists i would accept it. She's really happy with you and that's why she wants you to sort the ceiling.
I just feel that if she sorted it out herself she may get ripped off (sorry, I meant over charged) I think I'll charge her £20 for the plumbing, so she's happy she's paid me...
That was my bug bear with a carpet shop i used to work for. The old dears have always used them so they'd inflate the prices. Its was shocking what they got away with. Sometimes it was triple the amount. I couldn't work for them any more cause of that. They were supposed to be Christians as well. Had that fish on the signs and vans. I just thought if that was my nan and i found out that happened i would go mental. Your a good man pal. Not many like us around.
All done, two coats vinyll matt on ceiling and two coats of soft sheen on walls and that cupboard was soooo heavy to lift back. Lights all fixed on as well.