Looking for DIY livery for 2-3 horses

Looking for 2, possibly 3, DIY livery spaces for a horse and a pony. Ideally one of the boxes would be larger than standard as the horse is 17hh.
Good all year turnout is a must, with the option for 24/7 in summer preferably.
Sandschool would be ideal, but could consider options without if there was one nearby.
Would consider part livery options at the right yard.
I feel I am a good livery, always attend to my horses twice a day and am able to provide references from current yard. Read more