Non-grid-tie set up here. 4 100 Watt Panels on mine, powers everything except for the propane. Generator for cloudy days. Total Cost: $2000 (wiring, kinda expensive MPPT charge, kinda expensive swing-capable brackets, kinda expensive inverter) already had the propane generator. After learning how to do this on an RV I've decided to never buy a stick home again since most states will require a grid-tie (which is the dumbest thing you can do)... So living in a trailer is the best way to live now.
My system cost about $15,000 via solar city for a 6kwh system. Austin utility paid me about 3000 and I got a 4000 tax credit. Last month my bill was -20 dollars. Looking back on solar, probably not the best financial decision but I think it's pretty cool and I will be able to run the AC this summer at 70 for a reasonable bill.
From June till September last year(pre solar) my energy bill was near 200. My financing is about 70 dollars a month for the next 20 years... I'm expecting my solar production to cover probably 70% of my bill. Since I'm paying financing plus utility hookup(mandatory $10), plus what ever I use after solar; I will likely not recoup my investment. Imho, it's more feelgood and a hedge against future energy price increases.
I have also noticed that I pay attention more to my consumption. I've debated on buying an energy consumption device like sense, but it seems like a toy...
The -20 bill was the result of having pleasant weather and not running the AC as frequently in April, plus it was a very sunny April... I'm pretty sure I will not have a negative utility bill in August.