Keep your eye on the site mentioned here http://www.tractiontalkforum.com/showthread.php?t=36398 some of the stuff is dead cheap if you can collect, there were three Triumphs and some Mascots that ended yesterday. A Mastiff is a big step up from a Triumph
That's the rub though - "if you can collect" - some of the larger firms won't let you turn up with a trailer unless you have paperwork/certificates to back up your credentials so you end up being forced to use their "approved carriers".