File on 4 investigates how Britain's homeless and vulnerable are used for cheap labour - tune into Radio 4 on Tuesday, 13 May at 8pm to find out more.
You can also listen online or download the podcast at http://www.bbc.co.uk/fileon4
Please enable it in your browser's preferences.
You can visit our support center if you're having problems.
We recommend upgrading to the latest
Please check your internet connection and refresh the page. You might also try disabling any ad blockers.