A Federal agency may consider purchase of buildings on a case-by-case basis if it has landholding authority and when one or more of the following conditions exist:

(a) It is economically more beneficial to own and manage the property.

(b) There is a long-term need for the property.

(c) The property is an existing building, or a building nearing completion, that can be purchased and occupied within a reasonable time.

(d) When otherwise in the best interests of the Government.