By using standard 2Watt Polycrystalline cells, available on sites like eBay, you'll enable yourself to build a 100 Watt panel for around $125. Some people even opt for chipped, or B-Grade cells, that produce the same amount of power but are defective by the manufacturer's standards (ie chipped corners, etc). With this choice of solar cells a completed 100 Watt panel may cost less than $70.
Solar Panel install - from start to finish! Follow along as I show you how I installed the Renogy 100 watt solar kit, which includes (besides the 100 watt solar panel) the Adventurer 30amp charge controller, and a pure sine wave inverter. Everything you need except for the battery to start powering your devices directly from the sun!