So far I’m working with a pretty bare-bones setup. My primary telescope is a Orion Observer, a 70mm f/10 refractor. My wife found it for free online a few years ago. Piggy-backed on it (with bungie cords) is a Gsyker 70mm f/5.7 that I got on Amazon for $80. It came with the focuser and finder mount broken, so they refunded me $20 for the trouble and sent a second kit.
Putting a 25mm eyepiece in the smaller scope gives a great wide field of view as a finder for the larger scope.
In the picture below I have my webcam imager installed in the big tube.