How do you look for quality in a scope?

1. Look at the plywood used. Some manufacturers use inexpensive plywood from the local home center.  Count the number of layers in the plywood.  A low grade plywood will only have 5 layers in 3/4" thick material. In addition, this "core" material is made from softer woods like poplar.  This means that the surface of your telescope may be easily dented. A quality plywood will have 10 to 12 layers for that same 3/4" and the core material will be made from birch or maple which are more durable hardwoods.   Plywood's stiffness and rigidity depend on multiple layers.  A high layer count will mean that your scope will flex less and that scope will look good for a very long time.
   
2. How are the joints made? Look at the corners of the mirror box and rocker box.  Look for nails holes that have been patched.  Nails will not hold a corner joint together. Nails only hold the box together while the glue dries.  A joint put together like this depends solely on the glue.  A joint made in this fashion also requires additional stiffeners inside the corners to prevent the box from coming apart. Mortise and tenon joinery, a long proven method of fine quality cabinetmaking, is the most effective method for providing you with strong corner joints.
   
3. What is used for the finish? Oil based finishes will yellow over time. Water based finishes will not (they are also more environmentally friendly).  Are there runs in it? Is the finish inviting and smooth to the touch?
   
4. Will the mirror stay put?  Will you need to adjust a sling?  Will you need to worry about the mirror bouncing up and down as you travel with your precious cargo?
   
5. How easy is it to make adjustments for collimation?  Is the secondary mirror clutched or is it just mounted on a bolt?
   
6. What is the focuser like?  Does it move smoothly?  Is there a fine adjustment capability?  Are there leveling adjustment screws on the focuser base plate?  Is there a solid material (not wood) behind these adjustment screws? Do you need to pay more (as an option) for a better quality focuser?
   
7. What is the altitude and azimuth movement like?  Check for stickiness as you start to move the scope.  This jerky action will foul your attempts to center anything at the eyepiece.
   
8. What kind of hardware is used for fasteners?  Galvanized steel, brass,  or stainless steel?  Are the screws that may need adjusting slotted for screwdrivers or are they hex head?  Slotted screws will wear and eventually fail (have you ever tried to get out a screw where the slots were destroyed?).  Hex screws are easier to drive and rarely fail.  Most materials will rust or corrode.  Stainless steel will not.
   
9. What is the overall look and feel?  Granted, you don't need to have a sharp looking telescope to provide great views.  But chances are, if it doesn't look good, it won't work right.  Attention to all fine details strongly influences the final performance of the product.
10. Check the ground board if you are considering GOTO and tracking for your scope.  Is it made of high quality laminates or is it cheap plywood from the home center? You want the best material here for consistent tracking and durability.  Are the feet made of pine or of durable hardwoods?  Pine feet will more quickly absorb ground moisture.