I have heard (info could be completely wrong) that there is an investment mafia, a group of certain people who controls the prices of property. Is that true?
Please share your own analysis about it
No one is ready to comment on this topic 
Not true.
You may say that there is an elite club of real estate developers such as Bahria, DHA and now Multi (plus many more in Lahore and Karachi) who have very effective control on the seller side, I don't think there is any such club or mafia on the buyers' side.
The buyer side is made up of (i) local genuine buyers who need a house; (ii) local investor class who revolve and move their investment funds between different schemes and societies and (iii) overseas Pakistanis (many of them in the Gulf region earning tax-free incomes) who can influence the market.
But (i), (ii) and (iii) don't act by collective planning at any level. They act on market sentiment and perhaps the same events may influence most of them in the same way.
Many of them jump on the bandwagon of a particular scheme when the market is going up due to factors such as a road, interchange etc. They start off-loading their investments in copycat fashion when the market is going down due to any adverse news.
But overall the real estate market goes up or down on the basis of the general views made by the media on national political situation, security situation, investment climate, incoming IDPs, law and order problems in Karachi, bombings, operation in northern areas, floods etc....
Yes some societies have dealers who promote a particular scheme but this can have very limited effect. For example, all the pro-Multi dealers even together cannot increase the price of Multi projects at this time when there is almost no buyer in the market.
Thanks very much Guru for sharing some good info 
DEFINITION of ‘Bandwagon Effect’ A psychological phenomenon whereby people do something primarily because other people are doing it, regardless of their own beliefs, which they may ignore or override. The bandwagon effect has wide implications, but is commonly seen in politics and consumer behavior.
You are absolutely right, there are groups playing in real estate trying to fetch maximum gains stating game…