I am scared of real-estate, mainly due to the fact that same product can have a different buy/sell price with 5 different people
Price manipulation is unlikely. After all, each sale will be recorded in the blockchain, including price records. The agreements between the buyer and the seller are recorded in a Intelly smart contract. And the seller/developer has full trust and clear understanding about when and how many tokens will be transferred to their wallet at what milestones.