I agree with Grant and Barry, you don't want to be sealing in moisture, and also it will have absolutely no insulation properties. Pointing is defo the way to go if it's looking a bit ropey. You can buy extra thick grinding discs for small angle grinders that are good for raking out.
Roof repair costs will depend greatly on whether it's tiles or slates - tiles are about a quid each and quite easy to change, slates cost double that and are much more tricky. If they're clay Rosemary tiles I advise moving house
Only kidding, but they can turn into a much bigger job.
Your mans prices seem very reasonable, so worth hanging on to him - we're a rare breed!
I just dropped in, to see what condition my condition was in
T/T: Inspire Monarch, X200 tonearm, Ortofon Quintet Blue. Phono: Project Tube Box CD: Marantz CD6006 (UK Edition); Amp: Musical Fidelity A5 Integrated.
Speakers: KEF Reference 3, REL T9i subwoofer. Cables: Atlas Equator interconnects, Atlas Hyper 3.0 speaker cables
T'other system:
Echo Dot, Arcam A75 integrated, Monitor Audio R852 MD speakers
A/V:
LG OLED65 G56LS, Panasonic Blu Ray, Sony a/v amp, MA Radius speakers, REL T9i sub.
KICKSTARTER: ENABLING SCAMMERS SINCE 2009