Rti to find unauthorized people staying at an address

In case it is a public trust, you can file RTI for getting the particulars of the trust. Aside need to go through the documents thereafter for justifying your locus standi. Otherwise if any nuisance is caused over there you can initiate legal action.

You can file an application under section 6 of the Right to Information Act, 2005 and seek relevant information from concerned Public Information Officer.

A private trust is not within the ambit of RTI Act.  If you have strong evidence, you can make a complaint to the commissioner and to the concerned PS and report about abuse/misuse of such trust property.  As social media is most powerful, take the assistance of some journalists on pay roll of some reputed TV.

In the light of the alleged illegal activities, the remedy lies in registering a criminal complaint. The RTI route would turn out to be inadequate. 

The RTI is about the transparency and accountability of public authorities.  A citizen has a right to seek that information that is available in the form of a physical material (public record) from public authorities and from those organizations that are having the substantial contribution of the capital from Govt.

RTI is never a remedy or concerned with redressal of grievances as misunderstood by citizens even after 12 years.  RTI is a road that may lead to a destination and not a remedy.