The most I've had at one time was 4.
But that was when I had access to storage. HS2 has now removed that because they've decided that not only do they want to land grab, it's not enough to just have a fence, no human can be within however many yards of the workings so about a dozen of us have lost our storage.
Now I've just two and one of those needs to go. I'd happily have more but the reality is that I haven't the space.
Sometimes it just isn't possible to have what you'd like
.