Rent payable after eAuction by customs department

We've leased our warehouse to a handling agent in Tuticorin. A transit cargo was stored and the importer has not turned up to clear the goods. Rental Agreement was with the CHA. They paid rent for 1 year and defaulted rent till date. It has been 6 years and we have filed a writ in madurai against customs to auction or abandon the material. The material is about to get auctioned. Will the Duty be paid on declared value or auction value ? Who is liable to pay the rent Customs/Buyer/CHA ? from the order date to auction as there was inordinate delay of 2 yrs, Can we claim rent from customs ?