Q. On the process of buying a property, can someone sign the “waver of conditions” during the 3 weeks or the nine days? Can you sign up for a mortgage then? Does it make a difference if it is a residential or a commercial property?

A. Shulchan Oruch (O.C. 551:2) rules that on the nine days we restrain from engaging on constructions that bring enjoyment. Mishna Berurah (ibid 7) quotes Magen Avrohom that this includes any construction that is not essential for normal living purposes, but is done for superfluous and gratuitous utility. Mekor Hachaim (ibid.) and Devar Yehoshua (2:73) permit the construction of structures for commerce or rental intent.

Horav Shlomo Miller’s Shlita opinion is that signing a waver of conditions or signing a mortgage for commercial purposes is permitted even during the nine days. For residential necessity, it would be permitted only in compelling circumstances where one can not wait until after Tisha Beav.

Rabbi A. Bartfeld as revised by Horav Shlomo Miller Shlit”a.