بسم الله الرحمن الرحيم
(Fatwa: 1460/1484/L=01/1437)
After shifting into a new house one should offer some nafl salah and then make supplication. Or some pious person is called for the supplication for prosperity and blessing. If you prepare some food and feed people to thank Allah without following any ritual and custom then it is allowable.
Allah knows Best!
Darul Ifta,
Darul Uloom Deoband
