Re: Electrical question(s) for people smarter than me.
Good rule of thumb is 12V on an inverter is extremely inefficient, not going into technical jargon but the "most efficient" inverters run on 48V and up. The lower the input volts the more the inverter has to double the volts to get to the output. I have a small (cheap) 1000W inverter running my garage. Enough to run lights and the odd drillmachine. Go for those portable solar jobbies, sunlight is free after all.