Ductwork is leaking on us

My spouse & I are selling our house so we can move our ever growing family into a house more suits our needs.  When we bought our home it was just the two of us & we agreed we would buy a fixer upper knowing we could do the work and making the house ours.  We went into it knowing this was a starter home for us & that we would buy a bigger house after we started having children. My husband and I currently have our house under contract which is so exciting, in fact just the other day the potential buyer had their inspector check out the house.  We had no worries about how that inspection would go because just about everything in the house was only 5 years old. Well, that has what we were thinking, but the inspection actually showed that we have leaks in our one of our air ducts. It was a tiny leak, yet it is there & it’s unsafe. We were both quite shocked to learn that our air duct was leaking.  We’d never noticed any sign of a problem, however, when we had our Heating & Air Conditioning professional out to the house to inspect the leak, he did confirm that there definitely a leak. The leak was so miniscule that it would take many weeks for us to even notice a problem. We were relieved that the potential clients had the inspection done because having that leaking duct can be dangerous to our family & the next family that lives here.  

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