Hi the mirrors make the telescope flat mirrors are cheaper than parabolic mirrors , but also what is the tube made from some are tin pricy ones are aluminium or carbon fibre , then you also have the mount some mounts are £1000s
Best value are dobs you get a lot of aperture for very little money , I went EQ mount as the tripod is more usable for me as a lot of my dark sites are not level ground , I got all my telescope second hand , the one I have now is an Orion Optics which has top class mirrors and a HEQ5 mount , cost new is £1400 I got it for £600
So keep looking on this site on the for sale section , also look on astro buy and sell UK , if you see something your interested in add a link and the members on here will tell you if it's good or not
But while your waiting sort out what you have and start to learn how to use it , lots of people start this hobby with binoculars you can see more than you think you will