I have a propane heated conventional WH with forced air ventilation fan. I have gotten two quotes from two plumbers for two options -
(1) current system replaced - $2700
(2) tankless WH w/ propane - $3000.
After reading a number of comments here, yours included, I think I have to do some more work on this. $1500 for a tankless compared to my quotes seems like a bargain at the moment.
My gas water heater in the attic is getting old. I’m thinking about buying a new one and setting it beside the old one. When the old one gives out I’ll be ready to install the new one in a few minutes. Extremely easy with Sharkbite fittings.