Not if you tell them its 20 odd years old, everyone builds trailers here and dont give a s-it, nor does the police, here is one I did earlier for a chaps garden cutting tractor, and a six wheel one for my boat.Don't forget IF you build your own trailer it will need an IVA...
Individual Vehicle Approval (IVA) for light trailers: help to get a pass
How to avoid the top 10 reasons light trailers don't pass the Individual Vehicle Approval (IVA) inspection.www.gov.uk