For reference I ride western.

I have a nice size round pen, but I’m thinking of building a small arena so I can work on more advanced skills at my own place but I’m not sure what would be an appropriate size because of all of the trainers I’ve worked with or facilities I’ve been to are high end or state of the art that I would never be able to afford to build! And their arenas are HUGE!! I realize that it’s their profession but I’m looking for some guidance for the something feasible for the normal person.

I thought about having the round pen at one end, and so I could double the use out of that, and just move a few panels to open up when trying to use some of it as an arena but that might be too much of hassle. I feel like I’ve googled and pinterested too much at this point.

I’m definitely open to hearing suggestions about what a decent size arena would be for the non-professional.