Question on water supply in Wowa

Hello dear community, have a question about the water supply in “Kalt und Warm” . It is like that, have a camping, which however has no water connection, would like to make it too right for with it then to be able to stand with it also sometimes on a camping place! It should be in kitchen “Washbasin”, bath “shower” and bathroom “Handwashbasin” each a tap for WARM and KALTwasser. The plant should run with pump and tank. It does not necessarily need to be autark or as that means, since I with the car anyway does not want to stand in the wilderness 😉 Everything on 12 volts doesn’t have to be, although I have a 12 volt battery 120AH in it for a few lamps. So you could let the pump run over there already……. To the water heating, this should already run over 240volt, because I am not so sure with 12 volts that it gets hot so fast, (are 3 people) that you don’t have to wait long until it is heated up again, that the next one can shower Which facility can you take here, who has already had experience with such a thing and can you run all the pick-up points over a boiler, read because of the pressure in the boiler the special taps must be and there is only one tap to a boiler????? Is that so??? What alternatives are there…Trumatherme, elgena kb3, kb6……… etc. I think there are some experienced campers who have had experience with it on campsites and which I am sure If someone is familiar with something like this or if someone has already installed something like this, could you give me a lot of help?? Perhaps with a plan or sketch?? Will not connect anything wrong and try to build everything so cheaply with the best effect………Dear greeting!