Lowes sells a hot water tank recirculation for a little over $100 bucks that sits on top of your water heater and has to be plumbed in. Works like a charm.

Don't get a circulating pump that attaches to the hotter tank because they cost too much to run even with a timer. Run the hotter from a sink close to where you want hotter first (guest bathroom or kitchen sink). They sell under sink circulators with timers and on/off switch.

An AOC recommendation is to fill a container with hot water and keep it in the refrig until you need some. Then just take it out, pour what you need and keep the rest until later when you need some more.

Villagers don't care
 

Villagers don't care about how much water they waste. I submitted a thread about all the sprinklers I have seen shooting water out onto the streets, running in the heat of the day, etc. and my concern for the amount of water being wasted. I was heartily lambasted and trolled by an overwhelming number of responses from Villagers who couldn't care less about the environment.

Why would you want to recirculare lheated water in a "on demand" system? Seems (to me) that that would be counter productive.

Hot water
 

I have a recirculation system with a timer on my tankless system. Ask your plumber.

Absolutely. Call Mike Scott Plumbing. They'll put in a hot water recirculating pump on the water tank and it works like a dream all the way to the back of the house! I paid $495 about 6 months ago.

If there is a cost, it is worth every penny for the convenience of instant hot water where and when I want it.

Hello,
I installed an electric heater under my sink. I bought 12 KW steibel eltron heater. A smaller unit will not work due to water flow rate ( I tried an 9 KW Rheem and it burned out in 2 months trying to keep up.
The 12 KW unit needs 6 gate wire on a dedicated circuit from the breaker box. I had an electrician run the wire through the attic for me ($300). I bought 80 ft of the wire on line for $300. The heater was about $300. Plumbing fittings ~ $75. I don't use either hot water shut off under the sink (one was for faucet and one was for DW). I teed off the cold (I bought shark bite 1/4 turn shut off). One branch to the heater, the other to the faucet. Then teed off the out line from the heater; one branch to the faucet, the other to the DW.

Looks like it is not a Watts........

Access Denied

Thank you I’m glad to hear someone finally speaking up & addressing this. I bet our house in Charlotte I ran 2 to 3 gal. everytime I wanted hot water. For one thing most hot water heaters were in garage (or most water heaters were) Tankless Water Heaters are just as bad or worse I know that’s what I have now. Thanks for posting this!

Those "on demand" systems seem to be more like "on demand when I feel like it". LOL.

It is obvious that most people replying here really don't understand my original concern. They keep talking water tank, on demand doesn't have a tank. I will be calling a plumber and asking the question. I will start a new thread looking for plumber recommendations. Thanks

Welcome to TOTV

Who are you to call hyperole?

I have a tap under B/r sink which fills container. Takes about 3/4 of a gallon for warm to get there.
I also have an outside storage tank that take diverted bath/shower water from upstairs which I also use on garden.
In winter when full it diverts to main drains.
Also collect rainfall in storage butts from shed roofs.
At our last house we collected rainwater from house roof guttering into underground storage tank which pumped water into house too flush toilets, and also irrigate garden.
Get your own plumbing sorted, and shove your hyperbole where the sun don't shine!