It really depends on what you are trying to do. Usually you want a proper sized battery bank for the inverter to run what you want to be able to run when dry camping. Normally, you use solar to charge your batterries, and use your batteries to run inverter. Depending on size of inverter it may take very large cables to your batteries and recommended shorter then 4-5' run in those cables. It really depends on what you are trying to accomplish though, ymmv. Great article I found here
http://www.macandchris.com/introtodrycamping.htm