Mine is a very basic 16" dob, and no....... telescopes don't need to be expensive because there are many alternatives available these days. It depends on what type you buy. Refractors and electronics/goto..etc, etc....will add to the cost per inch. If you nix the fancy stuff/high dollar mounts....telescope prices are very modest. IE....My scope costs less than many 4" refractors selling today!! I've seen mounts that cost much more than I have invested in my entire telescope!! It depends o what you want....
When it comes to cost per inch of aperture, basic dobs offer the biggest value. For example, I just bought a new 8" LightBridge scope last week. With my sons interest exploding, I wanted to buy something small/light that I could easily plop down in the backyard so if the urge hit to take a quick peek at the night sky, I wouldn't hesitate to take it out. My new 8" scope only cost $400, and with an 8" mirror......it has a very real light gathering capability. When it comes to telescopes, aperture/light gathering ability is everything. (pretty much)
http://www.telescopes.com/telescopes/meade/8197+8198+8268+4295045938.cfm
One can easily find a 4"-6" dob in the $200-$300 range. Just be sure to do a little research and steer clear of those cheap/crappy department store telescopes that advertise
"600+ power". When it comes to astronomy, it's all about aperture......not power.
This is another site that sells modest scopes that really work..........
http://www.telescope.com/control/main/
There are a bunch out there.......
Not to be repetitive but....avoid those department store scopes at all costs!!