Send them an estimate for all the damage, they are liable for any faulty equipment, you paid for a service that was not done properly, ask the Manager for there insurer's name & address, get his full name as well & tell him you have spoken to the legal team with your insurance company & this is what they have asked for, if you need a fully computerised assessment let me know you details via pm,
As already stated get some photos,
Hope this helps,