I think I have the same generator. The cost also depends on when you purchase it. I was lucky in that I purchased mine in the off season - mid-summer when it was on sale for something like $450 at Home Depot. Try to purchase one now and you'll pay full price.

A buddy of mine actually also purchased a high-end spitter that hooked up right before his fuse box, so he just plugs the generator directly to that and switches the power off the grid and to the generator. That way he doesn't have to run power cords all over the place. They turn off all non-essential items and run the house off the generator. When the power comes back on, he just flips the switch off backup and back to the main lines. I'll see if I can get a picture of it.

--Ed