Is this amplifier any good? Whats the estimated price?

is a very good pre-amp aka equaliser.
need to add a power amp to run
headunit --> eql --> power amp --> speaker

If i sell it, is there a value to.it?

depends on your offer price.
down side is moden car had no space to mount in dashboard . hifi players don't like to use equalizer.
it is a good equalizer , y not self use.?

Honest opinion.. not many ppl use the Eq as now days cars radios are built with Eq in it...

On the other hand.. perhaps try ur luck on mudah.my and see.. provided price ain't high... dapat 100 pun okie lah broo...

Only EQL made by Audio Control got 2nd value but this I dont think so have one..