Voltage converter for Traction Battery Generator

My power has been out since a storm swept through the DFW area Thursday. I've read several threads about using ones Prius to generate power. The easiest method I read was to just connect a 1000watt inverter to the 12volt system. However, this doesn't provide enough power to run a freezer and 2 refrigerators. The small amount of info I've read on using the traction battery system for a generator seem to revolve around buying a used commercial UPS. There has to be a more compact less expensive way to go. 3kw 12volt inverters are easy to find.

Anyone know of a 230volt dc to 110volt ac converter that will generate 3kw running and up to 4 or 5kw surge, that doesn't cost an arms and a leg? Perhaps there a unit designed for usage with solar panels.

 

That's why I'd like to put together a plugout for the traction system. If I can get this put together I'll have my electrical panel replaced and in the process have a sub panel with a manual transfer switch for running off generator when the power fails. My electrical panel is from the 70's and I am planning on replacing it in the next year or 2 anyway.