I am changing out a bit more plumbing and debating if I want to prep for a tankless water heater as well. It will be NG, and mounted outdoors. I live in Houston, so groundwater is a bit warmer than most places, and family is currently 3 with no reasonable chance of being higher than 4. Two bathrooms, only one tub, so 3 lav sinks, one kitchen sink, dishwasher, washer, two showers and a tub. The numbers work out that unless the clothes washer is on a hot load, somebody takes a bath and a shower while somebody else does the dishes, tankless will be adequate.

Anyway, what are some good reasons to NOT go tankless. I know there is the cost, but I also want the space as my WH currently uses a pantry area in my kitchen that can be used to store cleaning products instead. All of the plumbing will be CPVC accessible in an open crawlspace.

So what am I really missing? Is there some kind of nasty maintenance I don't know about?