As a real estate agent practicing at a time when people can't buy the perfect houses because of the lack of land availability, I found this article very relevant and hence saved it for the viewers of my blog.

Some of the remedial measures, which may be implemented to remove Vastu Doshas are as follows:
1) Perform Ganesh pooja, Navagrah Shanti, and pooja of Vastu Purush before formally entering the premises of your home or office.
2) Perform the Navachandi Yagya, Shantipath and Agnihotra Yagya to get rid of Vastu Doshas.
3) Take a Vastu Purush idol, a Nag (snake) made of silver, a copper wire, a pearl and powla, wrap all these items in a red cloth along with red soil and keep it in the Eastern part of the house.
4) Wrap some red sand, cashew nuts and powla (coral) in a red cloth, and keep this in the Western portion of your house on a Tuesday, and worship it with incense for establishing a peaceful atmosphere in your premises. If certain old buildings need to be demolished, taking the permission of the Vastu Purush by performing the prayer prescribed in the Vastu Shastra is imperative.                                                
5) After demolishing a structure and during reconstruction, make sure certain old items like the main door or gate of the compound, any old earthen pot or certain kinds of old furniture should not be reused.
6) It is important to worship the doorstep everyday, where you stick the symbol of a Swastik, a design of earthenware pot, or Shubh-Labh, etc., with rice and kumkum. Also, while entering the house, do not let your feet touch the doorstep.
7) Rakhshoghna Sukta jaap, Hom(havan) and anushthaan need to be performed on a regular basis for purifying the home atmosphere.
8) “Om Namo Bhagvati Vastu Devtay Namah” is a very efficacious mantra for Vastu remedies. Reciting it 12,500 times – beginning on a Tuesday – minimum 108 times everyday till it has been recited 12,500 times would be very helpful. At the end of the anusthan, perform the Dasamsa Hom.
9) Worshipping the Vaastu Purush on a regular basis is important for maintaining harmony in the home.
10) Certain problems can be caused if the South-West corner of the home is cut or not properly shaped, and to nullify its adverse effect you have to perform Pitru Shanti, Pindadan, Nagabali, Narayan Bali, etc.
11) Performing Rudri every Monday and every Amavasya day may be useful in maintaining a peaceful atmosphere at home.
12) Keeping a photo or idol of Lord Ganpati in the house can bring peace and prosperity.
13) It is absolutely essential, from a Vastu point of view, to have a pooja room in the house.
14) The Griha Pravesh, or house warming ceremony, must not be performed without first performing the Navagraha Shanti pooja.
15) A house which has been lying vacant for some years should be occupied only after doing Vastu Shanti. After doing Vastu Shanti, do not let the house remain empty for more than 3 months.
16) If you have an underground cellar, make sure never to leave it empty.

17) Even the room which is in the South-West portion of the house must never be empty.
18) For maintaining peace and harmony in the house, light a lamp every evening near the drinking water pot in your home.
19) Perform the Griha Shanti pooja every year to nullify the effects of the sinful things we do, knowingly or unknowingly, in our life.

Info courtesy - Yahoo! Lifestyle India | GaneshaSpeaks