Soon to be new rider, and have questions!

[ttocs84]

Well to be honest, i don't ride yet. I have operated dirt bikes for years, however i do not yet own a bike. I found this forum while doing research on bikes and safety courses. I have been considering purchasing a bike for a while and think that the gz250 would be a good starter bike for me. i do have questions however, after having been reading these forums for several days now, some of my concerns might not have been covered yet, so here goes.....

I want a bike, for two basic reasons,
1) I want to cruise and enjoy the ride, i am not looking to race around town, and don't personally prefer the sport bikes(crotch rockets)
2) I want something that will save me fuel costs, and the idea of 70mpg or so sounds great. See i drive approx 90 miles a day 5-6 days a week for work, even though my old ford gives me 19-20mpg that still costs me quite a bit.
My plan is to purchase a brand new gz250 from the local dealer that way its new with a warranty, plus i can finance it since i cant afford it outright. This being said, i'm still in the research phase, plenty of time to change my mind or get different viewpoints, that's why i'm here.

What is the average life expectancy out of these bikes? i wouldn't want to finance something for a couple years if i cant get that kind of mileage out of it. I am mechanically inclined, i used to own my own auto repair shop, and as such i am usually a stickler for proper maintenance. is the life expectancy of these bikes any different than other bikes, maybe say twin cyl. bikes or other brands?

Also, this is a big deciding factor, how will the gz250 perform in sand? I live back in the woods, down about a half mile dirt road, and by dirt i mean soft, close to beach sand in some spots. the entire rest of my ride is 45 miles of 2 lane highway, but if i cant get to and from my house, than this whole idea is moot! My uncles, both experienced riders for years, have said that if careful i could manage(with practice), but i am curious what you all think.