I just ran across this vendor of Solar & Wind generator packages suitable for RV installations - the prices look VERY good for Solar panels made in Germany... They use multiples of 100 watt panels
$215 for 100 watt system w/controller
$390 for 200 watt system w/controller
$545 for 300 watt system w/controller
Solar Panels | WindyNation.com
I haven't done business with this company, but the kits appear to be well thought out with most all you'll need to add Solar charging...