Roofer recommendation?

Hi folks,

Have a leak in my roof and need to have it looked at but wary of being ripped off by carrying out unnecessary work and spending more than it needs.
One person has already looked at it ad not managed to fix it- so it might be a tricky one- seems to be coming in via a chimney that was block up a few years ago- started as a small amount and now has progressed to being more of a problem.
Only wet patches on the ceiling but I reckon a few heavy rains and it might start dripping.

Any recommendations- I am in West London- W3.

This recommendation should be more successful than my camera one!
Cameron Elkins 07970192544 Based in Borehamwood but travels.
He has worked for people on here before, very reasonable.

Do not get him on the subject of bikes he will be there all day!

Cheers, will give him a call.