For my purposes, with a non-standard foot, the only option is a pair of custom-made summer hiking boots. I made my first Camino from Barcelona in the best-fitting off-the-shelf boots I could find. Still, my feet were extremely unhappy the entire way to Finisterre. For my second walk - Barcelona to Rome - I invested in a pair of custom-made boots. They cost $1200 including custom insoles to fit my flat feet, but they made all the difference. Considering the cost of the flight from the U.S., equipment, food, albergues, hostels, and all other expenses of both trips, the cost of the boots was relatively minor. I had them resoled after Rome, and will use them for my next Camino from Almeria. I can't wait.