Real estate business has nothing to do with construction, I understand. If there is no separate notification for employees in the real estate industry, you can follow the minimum wages of shops and commercial establishments. What is important is that the wages paid to your employees should not be less than that payable to 'similar' kinds of work in other scheduled employment. Even the salary of sales promotion employees would be okay for persons who undertake to convert a lead into a deal.
In addition to the law relating to minimum wages, you have to follow other laws like ESI, EPF, etc., depending on the number of employees employed and the salary that they are paid.