That’s awesome! How many seed potatoes did you start with?

This right here. I bought their security bit set and, true, I’ve only ever opened the case three times in the few years I’ve had it, but in those three times nothing else would have worked without a more destructive solution

Some vertical planters might go a long way in maximizing space. I would plant a lot of vines (peas, cukes, squash, beans, etc) on trellises all within that border hedge. Maybe one side could be an herb/greens wall with tiered planters

There’s a pretty lively community around balcony gardening. I’d maybe look to them for inspiration on maximizing the space