I don't think new trailer regs can be retrospective. The trailer may have a manufacture date on its plate. It mat be that a trailer is obviously older than new regs.
The only thing relative in that link is
Trailers built after 29th October 2012 need to be approved by the DVSA
Type 01 and 02...
Apparently some of the 'Super grades' are ethanol free.
I'm sure a Googling would identify them.
If you read you car's handbook it will tell you what level of ethanol is safe to use. My runabout is a 2007 Suzuki and that is OK.
Using the hydraulic system could bite you if you ever have an accident. The insurance company will step back, but the plod won't.
The argument is that cable and rod brakes work. Hydraulic and electric brakes can stop working, without you realising. The answer is to buy the back plates and...
Well you tried, but people want to talk about what they would like.
He could always build a punt like Dylan Winter did. Building your own little boat is great for the soul.
Look about for wood/epoxy dinghies like Fyne Boats or Selway Fisher kits. They are pretty, durable and very light. Usually...