Not sure if you bought a generator yet, I have a 6000/7250 watt DeVilbiss brushless with a 10 ckt gen tran switch that we put in 10 years ago. It does just fine when powering a oil burner for furnace, oil burner for hot water heater, forced hot air heat, some inside lights, an occasional hot plate and coffee maker and some outside lights and outlets for charging phones. (if folks without power will be joining you, make sure your bathroom fans are on the gen-tran switch, nuff said)
After having gas in my gen and storage tanks go bad several times even using Marine Stabil, I
converted my Devilbiss to a tri-fule propane last year. Now I hook up a Worthington 40lb propane tanks and get 8-10 hours per tank (or 5-6 hrs on a standard BBQ tank) running at 1/4 load, or 1/2 load when the hair dryers come out. I never saw the gen tran meters go above 3800 watts no matter what we ran in the house.
The advantage now is I can use LP or Gasoline, or natural gas if I had the hook up, so no waiting in lines for gasoline or gas storage issues. It took 2 tries to convert the generator, as we found the mother of all mouse nests in my engine cooling fins and they ate through the coil wire. Peppermint abstract and moth balls have sent those wire chewing bandits to my neighbor's house. His generator doesn't start now.
My new strategy is to move up to a slightly larger, automatic standby generator. After researching all the standard models like Generac, Kohler, B&S, Cummins-Onan and Winco models and forums I am close to deciding on a Winco 8k stand by generator. Winco makes a 12k with a Honda GX690 24HP engine, but the LP consumption of 1.6 gl per hour concerns me. I came across forums that had small engine repair veterans warning folks about the Generac and Kohler quality and service nightmares. I am not sure how often these really happen, but I cant find a bad review anywhere on a Winco Standby generator. They are commercial grade, not residential and they are not cheap. (check out
http://www.mytractorforum.com/ these guys post great points on a variety of engines and generator models etc..)
For portable I would buy an efficient tri-fule model or look at
converting a gas generator with a LP kit. 5k or 6k watts may be the right size. Buy a really thick chain and quality padlock too.
For home standby? I would talk to some electricians you trust, check the forums for the specific models and engines. Try to find folks who have used their stand by gens in multiple storms, vs just installed them and saying how nice they look
Hope this helps, Good luck, and don't forget those bathroom fans!