of the tax, and to provide guidance to the public. 403. Federal-State tax conferences Not less than once annually, the Secretary shall host a conference with the sales tax administrators from the various administering States to evaluate the state of the national sales tax system, to address issues of mutual concern and to develop and consider legislative, regulatory, and administrative proposals to improve the tax system. 404. Federal administration in certain States The Secretary shall administer the tax imposed by this subtitle in any State or other United States jurisdiction that— (1) is not an administering State, or (2) elected to have another State administer its tax in accordance with section 401(g). 405. Interstate allocation and destination determination (a) Destination Generally The tax imposed by this subtitle is a destination principle tax. This section shall govern for purposes of determining— (1) whether the destination of taxable property and services is within or without the United States, and (2) which State or territory within the United States is the destination of taxable property and services. (b) Tangible Personal Property Except as provided in subsection (g) (relating to certain leases), the destination of tangible personal property shall be the State or territory in which the property was first delivered to the purchaser (including agents and authorized representatives). (c) Real Property The destination of real property, or rents or leaseholds on real property, shall be the State or territory in which the real property is located. (d) Other Property The destination of any other taxable property shall be the residence of the purchaser. (e) Services (1) General rule The destination of services shall be the State or territory in which the use or consumption of the services occurred. Allocation of service invoices relating to more than 1 jurisdiction shall be on the basis of time or another method determined by regulation. (2) Telecommunications services The destination of telecommunications