There is two 40 gallon gas water heaters that they are looking to replace and only wanted options for tankless. I took a look and everything in that area will work for a tankless we will have to modify the metal venting going up and also the roof penetration as well as modify the gas and the water but this is pretty typical when it comes to a tankless install she said she’s going to talk to her husband and let us know after he gets home from work