Yeah but there are plenty of photo instructions online and all you need is a extension cord, preferably grounded, and a 6 outlet power strip. I can get both at harbor freight for $4, so my thermostats never cost me over $60. I used to buy them pre-wired, but it's so easy i can't justify paying someone $20 to do something i can do in 3 minutes!!!
Oh yeah, but i have bought from rich more times than i can count and he is a GREAT person to deal with. His Rancos run about $85 shipped depending on location.
that 20 bucks is worth it for my piece of mind. My dad taught me never to mess with something i don't fully understand, electricity is one of those things.
If you feel confident about doing it yourself, go for it though. i just dont share that confidence.