Good point Anke, and of course will be lower for an unbraked trailer than for braked. For example, my wee Fabia can tow 750kg braked, but only 450kg unbraked (the caravan websites don't usually mention this, as caravans usually have brakes, but you can find the data on parkers.co.uk if you look hard enough!).
The 6 ft and 8 ft Ifor trailers weigh 156kg and 218kg respectively, so realistically with the big one I should only tow about 230kg of sheep..... i.e. about four of them!
Oh, if you do get the Ifor, go for the wider 'floatation' tyres. They're a huge help when towing around fields etc
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