Would like opinions as to whether this is a deal breaker-our boiler is as old as the house (we assume)-so about 40? It works okay and we haven't seen a reason to replace it yet. However-now we want to sell the house, and I know that boilers can be of concern to buyers when they are over a certain age. I have read on here that you can buy a new boiler yourself and then get someone in to install it (not sure of exact cost but cheaper than getting Scottish Gas to do it all). Would it be worth it??