I've been doing ameteur astronomy with some vigor for about five years. This year, I bought a scope. While having a ten inch scope is better than having a six inch scope, it is becoming very clear that having a dark sky site to view from with a four inch scope is better than having a ten inch scope in downtown Detroit (more or less where I live). From my back yard, M87 (a galaxy) is simply not visible in my 10 inch. From a dark sky site, it was visible to Messier, who would have killed to have my 10 inch scope. He used something like a three inch refractor to put his famous list together. He lived before Edison invented the electric light. Even in 1930, downtown Philadelphia was a decent dark sky sight. The Franklin Institute has a couple very nice 20 inch scopes mounted on the building. Today they're good for looking at Jupiter, The Moon, and The Sun. This has been fixed since then.

That said, there is an $80 filter that saves a class of object for my even my front yard (which faces a shopping center parking lot with flood lights). It's the Oxygen III filter. With it, you can see nebulae. I saw M16, the Eagle Nebula, from my front yard, even though I had to aim the scope between the lights in the parking lot. The narrow band filter does not let anything through that wasn't emitted by this excited gas. It is recommended that you have at least an 8 inch scope for this filter. I've had good luck with one on a 6 inch refractor. For my front yard, a thick black cloth to put over your head helps block out the stray light.

Object types i've seen this calendar year: The Sun (use a filter or projection, please), the Moon (I use a moon filter which blocks 90% of the light with my 10 inch, and it's still too bright), the other planets except Pluto. Ceres, and a couple other minor planets. Stars, double stars, double double stars, galaxies, nebulae, clusters - open and globular, and comets. Not once have i looked for heavenly bodies through neighbor's windows.