Outside propane hook up?

Many CampChef stoves can be used via regulated low pressure.
CampChef makes a hose just for that http://www.campchef.com/rv-connection-hose.html
mbsturgis.com is a source for model 250 quick disconnects as well as http://www.gashosesandregulators.com/propanequickconnect.html

Generally there are 3 propane pressures, regulated low (less than 1 psi), regulated high (greater than 1 psi) and container pressure (unregulated, varies with temperature, 100 psi @ ~60F, 200psi @ 100F,60 psi @ 30F).

Most grills operate via regulated low pressure, a Coleman stove is regulated to 15 psi.

A big buddy heater has inputs for unregulated propane and regulated low pressure.

Thanks for the info. I would like to attach my 2 burner Campchef stove to the line, will it work fine on the trailer system if I remove the regulator from the line? I have added a chunk of hose to the stove so I could get the propane tank out of my old cook tent so all I should have to do is remove the chunk of line with the regulator on it and use the other line to connect to trailer.

Good to know about the grills with the green bottles, I was all set to buy one of these for the trailer. Guess I will have to find a trailer specific low pressure grill.

In the world of Propane there are two types of "Taps" High and low pressure.
High pressure is over 100 PSI Low pressure under 1/2 PSI.. DO NOT CONFUSE THEM

A grill with it's own regulator needs HIGH pressure
A grill designed to connect to a RV's low pressure port needs LOW pressure.

Beyond that I will leave it up to others. And no I can not list models of the latter.. And models of the former are too many to list. (Any portable Propane Grill save those SPECIFICALLY designed to be used on an RV's low pressure port)

most of the ones designed to use Low pressure are also designed to attach to a bracket on the side of the RV. I truly do not want my grill that close to the RV.

deleted

You could put another shutoff valve in the line from the onboard tank feeds that quick connect.

There is a standard propane quick-connect fitting with ball valve that RVs use. It's pretty straight-forward to install one, and most modern campers come with them.
I went a little further and mounted two of them at a more convenient location.

Remember that this is low-pressure propane, so your appliance needs to match that. Appliance that attach to a small propane bottle are high-pressure devices that have built-in regulators. Many of those have adapters that by-pass the regulator for low-pressure use, but many do not.

Surprised there is not a quick disconnect fitting on it already. The regulator on your tanks acts as the grill regulator, you just need to make sure your grill does not have a regulator.

I would seek out a plumber or someone certified to work on gas systems to install the fitting.