Here's a high-risk suggestion.
Beginners approaching the hobby for the first time often think in terms of spending money, not investing it. They figure that whatever they spend, they stand to lose—which, with good equipment, is only partly (small partly) the case. With good equipment, it may barely be the case at all.
Compare the prices of new premium brands, such as Starmaster or Tele Vue, with what sellers ask for them used on Astromart. In many cases good used scopes don't lose much value. And if the scope is third-hand instead of second-hand, what's the discount for that. Maybe about zero.
Price aside. What do you want as a beginner. Minimum hassle. Maximum intuitive-to-use-it-ness. Genuinely exciting views. And an instrument which will make it easy to find things, not frustrating, while you learn the sky. That last part seems to me to have been under-emphasized in other posts on this thread.
Where does all that point? If you don't have much cash to speak of, then the 8-inch f6 dobs that others have mentioned may be the way to go. Probably a better choice than an introductory achromat, which is likely a long-term source of expense, because if you end up liking the hobby you will replace it with something better.
And starting with the achromat, you have less chance of liking the hobby. It compromises on both view quality, and ability to see dim objects, which is a big compromise. But most refractors do offer focal lengths short enough to maximize the ability to learn the sky--a big plus.
And the dob has compromises too, (everything has compromises). Collimation scares some people. Cool-down can be an issue. And an 8-inch f6 dob shows only half the sky or less compared to most refractors, so it's harder to find things and learn.
Here's the high-risk strategy. Buy a used premium APO refractor, a Tele Vue or Takahashi, on an alt-azimuth mount. You compromise on only one thing: dim deep sky. Everything else is maximized, low hassle, ease of use, retained value, stunning, amazing views of moon, planets, star clusters, double stars, many nebulae, and one galaxy (M31, you can also see some detail on maybe a few dozen other galaxies). And most important, learning the hobby and the sky is maximized.
Where's the high risk? It's only a low-cost strategy if you don't like the hobby and sell the instrument. And if you start this way, you are not going to do that.
Steve
