JoeH has the best answer I think, there are several makers of "extend-a-stay" propane kits. Marshal(MEC), "Sturgi-safe"(MB Sturgis), JR Products and Camco also make similar kits.
I would buy a deluxe kit with the brass "Tee" that connects directly to the tank or cylinder and then the house system is connected to the other end. In the middle of the "Tee" is a fitting that is the same as the connection on a 1lb cylinder, a hose to connect your BBQ and a hose should you wish to have a extended stay (100# cylinder) to feed the house.
There are a variety of ways to hook these adapters up to your RV and a large variety of fittings to hook hoses up almost any way you want, including quick disconnects.
If you would like more specific information, I would be happy to copy the pages of a catalog and post in this forum. PM me with the request. Of course you can Google any of the names I listed above and get the info direct from the Mfg.
"I travel not to go anywhere, but to go. I travel for travel's sake. The great affair is to go". R. L. Stevenson
David Bishop
2002 Winnebago Adventurer 32V
2009 GMC Canyon
Roadmaster 5000
BrakeBuddy Classic II