Trying to determine market value of a D Sachs phono stage, please help!

The method proposed to get a rough idea of the Value is viable and one worthwhile considering. 

Alternative, reduce purchase value by 50% of paid price, if the model is upto 3 years old.

Above 3 years old creep price down towards a 60% reduction to counter offers of a 70%—80% reduction. 

My last Phon’ sold, a commercial SS model, that proved to be very very poor, went quickly when reduced to more than 50% off the retail price. I paid near £1500 to have that lesson. 

Have had a similar experience with a early model Hana Cart', a big outlay to be immediately uninspired. 

Anything worth it’s salt is never sold on when I own it. 

Whatever the original retail-50%, start by adding  15%. Begin subtracting that amount if no interest lingers.

Here ya go! Check out the sold listings!!

https://www.hifishark.com/search?q=Don+Sachs+phono+stage

Thank you, everyone!  This puts me in the ballpark, which was all I needed.