Looking to buy a portable LPG generator. Any type of brand I should be looking into?

You will have to decide on whether you want a pad mount or portable generator, as well as automatic vs manual startup and transfer. $700 will be used up quite quickly on just the generator. You should consider budgeting for installation of a transfer switch to ensure proper and safe connection to your home.

Most gasoline powered generators can be converted to operate from natural gas or propane fuel. This company offers conversion kits.

http://www.propane-generators.com/

There is a considerable difference in operating cost between the three fuels. Gasoline can not be stored for extended periods and can foul up a carburetor. Propane can be stored almost indefinitely, and natural gas is reliable as long as the supply is present.

http://members.rennlist.org/warren/propane.html

Purchase a reputable brand generator. Many of the cheap generators on the market are Chinese built and of relatively poor quality. I've seen far too many fail and the owners left with trash when repair parts are not available. Briggs & Stratton, Honda, Generac, and others have good engines. Parts and service are readily available if needed. If it says Made in China turn and run. You don't want it.

Read through my home generator page for more information.

http://members.rennlist.org/warren/generator.html