My flat is showing significant signs of water damage which appears to be coming through the gable wall. I'm thinking the pointing will need replaced and the cast iron drain pipe is damaged, so probalby that too. The gable wall provides regular access to vehicles and the flat is a two storey block.

I am very clueless when it comes to this type of thing. Am getting quotes.

For those in the know, what questions should I be asking, what sort of guarantees should I ask for, if any? and generally what to do!

I know this is a bit random, but anyone who could give advice - I'm sure I'll not be asking the right questions. Would you take a schedule of payments for this normally?

Get three detailed written quotes including exactly what they will do, list of materials (with costs), and make sure it includes removal of all waste materials.

It never hurts to also ask for the numbers of previous satisfied customers.

If this is too much hassle for them, they probably aren't worth going with.

Thanks - I hadn't thought of making sure they include removal of waste materials.

Could it be the roof / chimney? If the wall is cavity construction then it is unlikely the water is coming directly through.
I had water running from the boards behind the gutter, turned out it was a cracked tile.

However, if you have broken gutters, I think you may be on the right track, and they may be blocked also and water is spilling.
Perhaps if the gutters alone were fixed it might solve the problem.

Consider a guttering quote(s) from mainstream double glazing companies, many install new replacement guttering too. Their estimator might give you a honest opinion of the wall condition too since they have no direct interest in brickwork.

Don't share your suspicions of cause to a builder if you are not sure what the problem is e.g. if you ask builder to point the wall then they will, whether or not it is the cause of the water problem. Describe the problem to the builder and ask them to give an opinion - and to more than one builder.

Ask / Google your area for recommendation, or not, of builders.
Find a builder that can take care of all the work, some will only do brickwork, some only guttering.
You must do research to locate a reliable and responsible contractor.

If not done already, do web search of your general problem and of the same question you posed here, there are lots of message boards for household problems.

Get a written contract.
I would not pay up front, only upon job completion and satisfaction.

Could you take a bit of time to consider, to get your mind around the whole issue.

I hope this helps, best wishes.