Vaastu talks about living in sync with the natural elements so that humans live healthy and both nature and human co exits peacefully. Vaastu even specifies the kind of trees we need to plant as remedy. It is part of astrology, and it is also mentioned in Atharveda .
The base of vastu lies in the fourth house of the natal chart. The fourth house known as sukh sthan. It is the resting place and where we go tired looking for comfort and quietude.
To get the vastu right one should study the fourth house, his lord and the impact of other planets. And in case someone does have a correct birth time the same can be addressed using the prashna technique.
The secret it that if the fourth house is strong, one doesn’t need to worry about vastu. Or any correction.
But if the fourth house is strong and yet the native is having problems; in that case study the dasha.
So, one might think that if the house is strong, the dasha should give good results all the time. The dash is a reflection of our karma. Think of an athlete who is young and strong yet ends up in the hospital because of an injury. If he strong he should not have an injury. There are some people who never fall sick but viral infection hospitalizes him. Just like our body the Dasha can also have a malefic time going on. It will come to pass, as the house is strong but create some hassles.
IN such case one should study the dash lord and propitiate him. There is no need to make any big structural changes. I personally believe in praying to the lord and giving charity related to the planet and his house ownerships.
But if the fourth house is not strong in that case study the lordship and the connections. It happens that the fourth house lord is connected with twelfth house and the native has the combinations of living abroad. In that case the natal chart has promise that the native will not live in his country. Study the Dasha that will take him abroad.
But if the fourth house is not strong and the native will live in mother land in that case propitiated the fourth house lord and the dasa lord. An expert astrologer can tell by seeing the planets whether or not the living space will be fruitful. Always study the dasha .The dasha lord is supreme. Even the transit is subservient to the Dasha lord.
Else in government flats some occupants get promoted , some demoted and some keep living till they retire.
Please watch my video on the same subject on my youtube channel.