You need to recite these two prayers:

• Abbreviated Praise to the Twenty-one Taras, and
• The heart request of the Indian pandits for daily recitation called Quickly Receiving Blessings; Tara name and mantras that are taken from the Tengyur.

Recite these prayers for five months for success, not just for the sale of the house but for achieving enlightenment for the benefit of all sentient beings. Even if the house sells before the five months is up, you need to keep reciting for five months.