If the bureau has more than one property on which it was unable to obtain a bid sufficient to pay the upset price, it may, with the approval of the interested taxing districts and in accordance with the requirements of this subarticle, petition for, and the court may authorize, a combined sale of two or more of the properties, to be sold free and clear of all tax and municipal claims, mortgages, liens, charges and estates, except separately taxed ground rents, to the highest bidder, and that the purchaser at such sale shall take and thereafter have an absolute title to the properties sold free and clear of all tax and municipal claims, mortgages, liens, charges and estates of whatsoever kind, except ground rents, separately taxed.