“Principal dwelling” means any dwelling, whether owned or rented, and the land surrounding it that is reasonably necessary for use of the dwelling as a primary dwelling of the claimant and may include a part of a multidwelling or multipurpose building and a part of the land upon which it is built that is used as the claimant’s primary dwelling.

“Property taxes” means real property taxes, exclusive of special assessments, delinquent interest and charges for service, paid by a claimant on the claimant’s principal dwelling during the taxable year for which credit under this subsection is claimed, less any property taxes paid which are properly includable as a trade or business expense under section 162 of the Internal Revenue Code. If the principal dwelling on which the taxes were paid is owned by 2 or more persons or entities as joint tenants or tenants in common or is owned by spouses as marital property, “property taxes” is that part of property taxes paid that reflects the ownership percentage of the claimant. If the principal dwelling is sold during the taxable year the “property taxes” for the seller and buyer shall be the amount of the tax prorated to each in the closing agreement pertaining to the sale or, if not so provided for in the closing agreement, the tax shall be prorated between the seller and buyer in proportion to months of their respective ownership. “Property taxes” includes monthly municipal permit fees in respect to a principal dwelling collected under s. 66.0435 (3) (c).

“Rent constituting property taxes” means 25 percent of rent if heat is not included, or 20 percent of rent if heat is included, paid during the taxable year for which credit is claimed under this subsection, at arm’s length, for the use of a principal dwelling and contiguous land, excluding any payment for domestic, food, medical or other services which are unrelated to use of the dwelling as housing, less any rent paid that is properly includable as a trade or business expense under the internal revenue code. “Rent” includes space rental paid to a landlord for parking a mobile home or manufactured home. Rent shall be apportioned among the occupants of a principal dwelling according to their respective contribution to the total amount of rent paid. “Rent” does not include rent paid for the use of housing which was exempt from property taxation, except housing for which payments in lieu of taxes were made under s. 66.1201 (22).