The asset sale amount would be the contracted or agreed upon price for which the asset is being sold.
To determine a split between a building/asset value and land value, a realtor or an appraiser would be a good resource to assist you, as well as viewing the assessed values from a property tax statement (which may not truly reflect market value). Or if you had previously entered a split between the asset and land from when you first purchased the asset, you could use the same ratio if you do not feel that land or building values (separately) have increased or decreased that much, one over the other.
Asset sale expenses would be expenses associated with the sale of the asset, such as commissions, appraisal fees, broker fees, legal fees, advertising fees, title insurance, inspection fees, surveys, loan charges, or other fees paid on the buyer's behalf, etc.
To allocate costs between the asset and land, you would use a percentage allocation of what each asset value is as a percent of the total combined. For instance, if the asset and land were being sold for a total of $400 and the building is worth $300 which is 75% of the total value and the land is worth $100 or 25% of the total, then you would allocate 75% of the selling prices to the building asset and 25% of selling expenses to the land asset.
