bids are invited for custom bid for services - total lump sum amount for 24 months including gst presently at the rate of 18 percent considering service charges on pre disclosed estimate for part a of sor contract labour refer schedule of rates in tender document , custom bid for services - total lump sum amount for 24 months including gst presently at the rate of 18 percent considering pre disclosed estimate quantity for part-b-1 of sor works with material, machine and item rate service, refer schedule of ra.. , custom bid for services - total lump sum amount for 24 months including gst presently at the rate of 18 percent considering pre disclosed estimate quantity for part-b-2 of sor : resources on as and when required and during atr services and services..