Here's an article from the current Good Sam Highways magazine that will enlighten you on all the cool stuff you need or rather don't need when beginning rv-ing - remember that everything you put in adds weight. And not everything you need must be bought new - our leveling blocks are left over 2x8x10s that we had - cut them up into 2 foot lengths and they are perfect.
RV essentials: Everything you need for your rig’s maiden voyage
Joe and Vicki Kieva
Good Sam Club Highways
June 2009
Dear Joe and Vicki:
We’ll take delivery of our first motorhome in about two weeks. In the meantime, we want to buy the essential equipment we’ll need to enjoy our camping trips. What do you suggest?
Joe: When you buy a new rig, it’ll usually come with an electric cord, a drinking-water hose, a water-pressure regulator, a sewer hose, a few sewer-hose connectors and, possibly, a length of television cable. This is basic hookup equipment. But it won’t be long before you’ll want to go out and buy a lot more stuff. As a starter, we’d suggest getting even more hookup equipment.
Your RV will come with a 30- or 50-amp electrical cord, commonly 25 feet in length, to connect to a campsite’s electric power. I promise, there will be occasions when one 25-foot electrical cord won’t be long enough. Get a 25-foot extension cord to match the one that comes with your rig.
While not every RV park offers a 50-amp hookup, most do provide at least a 30-amp connection. So, if your RV has a 50-amp electrical system, you’ll need an adapter that allows a 50-amp plug to connect to a 30-amp receptacle. You’ll also have use for an adapter that does the same for a 30-amp plug and a 15-amp receptacle.
An improperly wired outlet can result in a shocking and sometimes deadly experience. Pick up a circuit analyzer, also called a polarity tester, while you’re at the RV- accessory store. Use the circuit analyzer to check the campground’s electrical outlet to be sure it’s wired properly. Do this before plugging in your RV’s electrical cord.
Some campgrounds, especially older ones, may not deliver the sufficient voltage of 105 or more volts for the RV’s motorized appliances. Get a voltage meter that can be plugged into a standard wall outlet. Keep the voltage meter plugged in where you can see it.
A drinking-water hose is used to connect the RV to the campground’s water hookup and for filling the freshwater tank, and you’ll appreciate the availability of an extra 25-foot drinking-water hose. This doesn’t cost much more than a standard garden hose. When you buy it, make sure it’s labeled Drinking Water Hose, and it won’t impart any tastes to your water. If you’ve purchased a used RV, buy a new drinking-water hose. You don’t know what’s been living (or dying) in the old hose that came with that RV.
A water filter is a personal judgment call. Most experienced RV travelers use two. The first filters out sediment. The second, usually a carbon filter, sifts out bad tastes, odors and some organisms. We recommend at least a sediment filter.
A sewer hose is used to connect the RV’s wastewater outlet to campsite sewer hookups and wastewater disposal stations. Sewer hoses are made of various thicknesses of vinyl material. The heaviest is the most expensive, but it will also be more resistant to penetration by sharp stones or thorns and least likely to cause an embarrassing moment.
We’d suggest getting two additional 10-foot lengths of sewer hose (or cut a 20-foot length in half). Install a male sewer-hose connector on one end of each hose and a female sewer-hose connector on the other end.
RV-park sewer hookups come with a variety of inlet sizes. Look for a sewer inlet adapter that will fit several sizes of sewer openings. A sewer adapter with a 90-degree shape will allow the sewer hose to lay flat on the ground. Cut about a 3-foot length of sewer hose. Attach one end to the sewer-inlet adapter and install a female sewer-hose connector on the other end. This assortment of sewer hoses will permit a quick hookup to the campground’s sewer inlet and easy connection of additional lengths of hose.
Vicki: You’ll add more stuff as you go along: tire-pressure gauge, stepladder, leveling boards and so on. Don’t forget a toolbox with some basic tools. And be sure you discover the joys of looking through RV-accessory catalogs, strolling the vendor aisles at RV shows and visiting RV-accessory stores. Joe is constantly finding things he didn’t know he needed.
I tried that option 
