Swap/sale car/s for Trailer/horse box

I have a lovely K reg, Mercedes 190E, it has leather interior and is the most comfortable thing I have ever driven. It is MOt'D until April next year, will be taxed for another 6 months from the end of this month,

also a Dhiatsu Sportrak, 1.6 petrol, K reg again, no Mot or tax just because I could not keep 3 vehicles on the road,

I am looking to trade for a Nice Trailer or Horse box, as I really want to be able to get out to shows and also move my animals between the various fields that I rent,

I would be very interested in a 3 horse lorry, with living preferrably, as I fear I would be over the weights in a trailer, and am thinking about my son< who is disabled having a place to be changed and sit in the dry. Thanks