What is the most auspicious date for buying a house according to Hindu astrology (Vedic)?

For purchasing a new house, an auspicious date is one on which the lunar day (Tithi), constellation (Nakshatra), and day of the week (Var) are compatible with the birth chart of the person purchasing the new house; therefore, while purchasing a new house, it is appropriate to look at a personalised auspicious time (Muhurat).

Considering the Tithi, Panchami, Saptami, Dashami, Ekadashi, and Trayodashi of the bright fortnight (Shukla Paksha), while Dwitiya, Tritiya, and Panchami of the dark fortnight (Krishna Paksha) are considered appropriate; similarly, among the Nakshatras, Rohini, Mrigashirsha, Chitra, and Anuradha Nakshatras are auspicious.

While purchasing a house, the days of the week, meaning Monday, Wednesday, Thursday, and Friday, should be considered auspicious. Meanwhile, when calculating a Muhurat based on a personal birth chart, the position of the 4th house in the horoscope and the transit movement of the 4th lord, the transit position of Mars — the significator of land, and the transit movements of Jupiter and Venus should be taken into consideration; whereas, inauspicious Tithis, eclipse combinations (Grahan Yoga), the Rahu Kaal occurring every day, and unfavorable transits of planets should be avoided.