Fixed Gears and Classic/Retro fixed gears are a unique niche.

Here is the 2010 and 2011 Bianchi Pista on Bicycle Bluebook.
https://www.bicyclebluebook.com/valu...product/20197/
https://www.bicyclebluebook.com/valu...oduct/3038649/

They aren't particularly kind on the pricing, $100 to $200. That seems low to me.

It isn't supposed to be a very expensive bike new. Perhaps a little under $1000.

We are in a unique bubble of bike prices, but that may be going away quickly too. However, there have been issues with the availability of new bikes.

Assuming it is in good shape, good paint, tuned, lubed, and ready to ride, I'd probably ask around $450, and consider offers down in the $300 range.