The most effective way to have instant hot water is to have several hundred people stay at your house. That way the water will always be in use and will stay hot - just like at a hotel.

Other than that, using a recirculating pump is the only way to keep water in the pipes warm. You also need insulated pipes.

Having "instant hot water, just like at a hotel" is such a wasteful demand. Good luck with it. On the other hand, telling your builder that you want the house designed so that the hot water lines are short, insulated and not oversized will get you hot water in a reasonable amount of time with minimal amount of water waste.

Another option is to consider what you really want. We designed our house so that the water tank (heat pump) was right over the master bath. This gave my wife 5 sec wait. The shower is more like 7-8 secs.

The other priority was kitchen. We put a tank under the kitchen sink so that is truly instant.

We had a recirc pump in the last house. It is fairly wasteful - even with an insulated loop. Now if you design a short loop and really insulate it well (and perhaps packed or foamed in an insulated wall anyway, then you can be alright. Even with our insulated loop, I calculated our standby losses (ie no water being used) at 10 times what a typical tank losses were.

Last option is an on-demand pump. Using switches or motion detectors, you run the pump only when use is likely. This can have failrly tolerable losses..

I have an on-demand water heater with a recirc loop on a timer (runs morning and evening) and it is great. My utility bills are low.

Another option is D'Mand Kontrol, which returns cold water on demand back to the hot water tank. This system is limited by the size of the home.

Planning now for a Pex manifold system to service eight baths and two kitchens in 8,700 sf. of living space Rather than re-circulation or multiple hot water tanks, the hot water lines will be insulated, so the water is tolerable. Insulation alone worked well with previous large homes with copper piping.