Repair to terrace - waterproof membrane
I have just read about someone else who has had trouble with work concerned with a waterproof membrane being fitted incorrectly. We are going to have to pay out approximately E5000 to our condominium administrator for our share of relaying our personal terrace (which is over the top of the underground garages), and work to the side wall of the shared garage entrance which is beneath our garden. The work involves fitting a waterproof membrane in both cases.The administrator has had several estimates and has settled on one. Before we pay out our major share (smaller contributions will be made by the owners of the other 7 flats) how do we ensure: a) That the work will be done by a reputable contractor (the administrator says contractors get their licence by recommendation from geometras and that in itself means the contractor knows what he is about!!!)b) That any work done is guaranteed and that the guarantee will be enforceable.My husband isn't as concerned as I am; I always see pitfalls. Also he is the one who has to try and communicate in Italian so it's easy for me to come up with all the queries I would like answers to, but it’s not so easy for him to get the concerns across. (My Italian is in embryonic stage).Keeping it simple, what should we ABSOLUTELY insist on knowing before we pay up the Euros?The administrator does seem a good one and other work currently being done (ie repair to the lift and general decoration) appears to be going ahead efficiently.The property is 8 years old. Don’t tell me to get my husband to query the original builder’s guarantee please (or there’ll be a divorce).