>>2662125yep anon above is right, 200mm is the diameter of the primary mirror (and not the tube) and 1000mm the focal length.
reflector telescopes are very cheap, you can get very big apertures for a small price (mine was about 500$). Thats because big mirrors are way easier to make than big lenses. But keep in mind that you also have to buy a mount to track your objects, and thats more expensive than the telescope you put on it.
The problems with mirror telescopes: its susceptible to temperature changes. You will often have dew covering your mirror during long sessions. There are heat resistances and fans to manage the temperatures inside your tube. (but you can do fine without them, your sessions will just be shorter). Also, the alignment of your mirrors will slighly change over time, or when you move your scope. It means you have to learn how to fix it. You dont have to do these things with refractors.
