As far as insurance goes, it really depends on your insurer and your record (as well as age, and who knows what else). Give your agent a call and ask for quotes. It should take a few minutes at most. I pay $140 every six months for liability and comprehensive. I don't have collision.
My mileage averages at about 45 mpg for mostly around town, with a fair amount of stop and go, and short trips. The most I have achieved was 55 mpg when I was cruising at 60 mph for a whole tank.
I purchased it for $1820 with 31k miles and a worn front tire. I have put about 5k trouble-free miles on it so far, knock on wood. The SV650S carries a small premium over the naked version, but I was glad to not have a fairing when I dropped it. I had to replace the handlebar, clutch lever, and mirrors, but I was out less than $100 to get it back to good-as-used.
I still love it every time I ride it. If I got an EX500, GS500, or similar bike, I imagine that I would want something a bit faster after a while. I haven't felt that at all with the SV. It is a bit fast for a first bike, but if you're careful and get to know its limits, you should hopefully emerge unscathed. Whenever I'm on an empty country road I like to practice hard braking, avoiding imaginary obstacles, etc. My longest day of riding was just shy of 400 miles, the last 150 or so on the interstate. I was a bit creaky when I got home, but after a beer I felt just fine. The interstate is boring, so I avoid it whenever possible, but it is happy staying at 80 mph. I change positions in the seat and shake my feet out every once in a while to keep from going numb.
I'm also 5'8" with a 30" inseam, and I can flatfoot it easily. It feels like it was made for me, or rather people like me.