Design of compost bins how should we space them?

My step-son is building 3 compost bins for me, one next to each other -- very simple rectangular ones, using chicken wire and heavy duty stakes. He asked if we should separate each from the next by 2' or so to allow better air circulation. On the other hand, that would make it harder to shovel compost from one bin to the other, and debris would inevitably fall down between the bins. So maybe they should adjoin each other.

Does anyone want to weigh in on how we should design it?

I have mine side by side as you have anticipated this allows for easy shoveling from Pit 1 to 2 to 3. Oxygen does not penetrate well in the pile when cooking anyway and usually in my neck of the woods the exposure to the outside air dries the pile too fast. So I like the side by side with occasional oxygenation with a pitch fork into the next bin.

I'm guessing space is at a premium in your neighborhood, I'd keep it simple and have the bins next to each other, and less distance to reach, like you mentioned...more room for garden that way too! But that's just me

Thanks! That's helpful. I was leaning towards a single bin, and what you say makes sense.