Yes, Charlie solar is expensive but I didn't pay as much as they're charging now for the Sunware panels. It's a MUCH better ROI to save power than to generate it. I have 160 watts total (mine are 20-watt panels) and an MPPT controller, but they're only running a 2.9A refrigeration load full-time and that's about what it takes (on-average) at 40-degrees North. On sunny days we run a surplus but we're on a power deficit if overcast. When cruising and running instruments and laptop and lights (and opening the fridge more) it doesn't keep up unless we run aux power. An inverter generator from Yamaha or Honda is worth considering -- much more cost effective than more PV-panels or built-in gen-set and quieter/more efficient than running your main engine at anchor.

BTW -- I found out by accident that a netbook uses less than half the amps of a full laptop. You should consider a netbook if you use computer-based navigation.