Re: Place hives at random or make a bee yard?
Do what is the most convenient for you. Have you ever seen a commercially kept apiary w/ 40 to 400 hives in one place close to each other w/ 4 or 6 hives almost touching each other on pallets? No robbing problems.
Especially if you anticipate a problem w/ bears you are going to want to keep your hives close together so building one fence rather than three can be done.
The answers are the end. The questions are the journey. Journey on.