I'm outside Thailand and want to hire a rental agent to manage my condos. What documentation will be required? Do I need to go the Thai embassy in my country to get the paperwork notarized?

What part of the Thailand are your condos in?

 

The first thing you will need is a strong contract with your agent, detailing who is responsible for what, and what/when the agent will get paid. You will also need a copy of their Thai ID card.

 

To manage your condos the agent will need signed letters of authority, and signed copies of your passport. They may also need signed copies of the blue house book and the title deed, depending on what you may ask them to do.

 

You will not need to get the documents notarised.