Yep, start by reading the trust documents. You might need to read them over very carefully several times before it starts to make any sense. Then go find a local lawyer who is familiar with the subject. If you can find the lawyer who drafted the original document all the better. I have no idea what you can or cannot do since I've never seen the trust document but typically there is a way to resolve disputes. A lawyer would have to be a complete fool to draft up a document that didn't provide for some sort of dispute resolution. A joint trust split between two brothers 50/50 with no dispute resolution is a bad idea so there has to be an out. Read the document and see what it says. Perhaps it has a mediation section or something like that. If the renters aren't paying the rent and your brother is saying it is okay then he is on the hook for the missing money. Of course, if you force that issue in court then there will be some hurt feelings involved. You might be able to get someone appointed by the court to monitor the trust. If the renters don't pay then the court will evict them.