What's a used Mini cost?

I've seen them go for $25 and up. Picked my mini up for $150. The mini has actually grown over the years. I think the original mini started with a 9.5" grate. Today's mini sports a 10" grate. Making most current accessories too big for it. I have the double scissor style hinge on my mini. Not a big fan of it. Going to purchase the new style band for it but will need to be cut down, bent, and drilled out to make it fit right since it's a half inch larger. The other alternative is adding a gasket between the egg and band. Lower draft door changed over to stainless at some point. Original mini also came with a ceramic fire grate. No stress relief cutout on older fire boxes. Non Tel-Tru thermometer. I'm sure I'm missing a few other things. Some stuff to take into consideration before purchasing a used mini