What is the value of a playing condition violin made by Grand Gerard 1800?

On auction violins of Jean Baptist Grand Gerard are doing badly. They sell in the range of $300 to $800.

In fact the value should be $3,000 to $5,000 depends on the condition and the sonority of the violin.

The violins of Grand Gerard are of inferior quality and workmanship, but keep in mind are about 200 years old, made by hand, and the tone is quite good.

Chris Christoff