There are a lot of places that will sell you a package, ie everything you need to get,setup. IMHO buy an oval dish and tripod from a reputable dealer and plan on HD. Heck go for a DVR too. When it is all setup at home, then simply duplicate that for your RV and cabin. Newer Direct equipment use SWM technology. That is a single wire that carries the signal for two receivers. It does requie a power supply to provide power for the LNB. I simply went with a bit older technology and run 4 wires from the antenna to the two places in my trailer. Works fine for us and saves a few dollars. I guess some day ill have to go SWM, but not right now.
A DVR will allow you to record hours of programming without the hassle of commercials. That isrobably 85% of our TV watching so for us it is great.
If you go direct be careful on equipment choices. Some of the newest technology is great for home, but can bedifficuly to setup on multiple TV's in a trailer.