When I asked my lawyer this question, his advice was that for a one-man shop, incorporating does not significantly affect your liability. If you are negligent, then they can come after you, whether or not you have incorporated. I know this differs from the word on the street. I made him say it several times, because it was not the answer I expected. Where it makes a difference is if you have partners. If your partner is negligent, then a corporation or LLC can shield you. BTW, he did not bill me for that consultation. There is really no excuse for asking a large group of non-lawyers instead of calling one on the phone for a few minutes.

.. but the specialized libraries aren't as mature. http://www.scilab.org/

First, don't completely rule out batteries. Rather than have the big generator running all the time, it can be better to run it every few hours to heat the house and recharge the batteries, and run the router/light/laptop off of the inverter. If you know which end of a soldering iron to use, you will do much better by buying batteries and an inverter than by buying a UPS, and you'll save money when it is time to replace the batteries.

Second, choose the right fuel. Gasoline is common and plentiful, but dangerous to store in quantity and a royal pain to extract from the gas tanks of modern cars, and that gas station down the street is often a lot harder to get to when you need your generator. Propane is common in rural areas, but essentially impossible to refill during a blizzard. If you heat with oil, it makes a lot of sense to get a generator that can run off of oil.

If you do store gas, buy an can of Stabil and use it.

Electric start is nice, but really increases the cost of the generator. And even if you test it weekly, it seems to fail when you need it.

Last time I checked, the Honda generators were much quieter than the cheaper ones. After days of operation, this does matter.

The dangerous, low-cost installation is to just get a male-male 'suicide' cord. Turn off the main, and all the circuits you don't want to power. Use the cord to connect the generator to a 240V socket (maybe the dryer, going out through a window), and turn on that breaker and the breaker for the circuit(s) you want to power. If the hazards aren't obvious, then this probably isn't for you.

The hazard of non-approved installations is that if you power the line to your house, it will may go the wrong-way through the transformer, and charge the line the repairman is working on to 13 kV. But only if there isn't so much load on the line that your generator gives up first, which is what usually happens when you forget to disconnect the main. (I've never accidentally tried to power my neighborhood, but my neighbors have.)

The problem with the cheap 'installation' is that you don't have an easy way to tell when the power has been restored. You can end up running your generator for hours before you look out the window and see that your neighbors house has the outside lights on...