Public spaces to hold dog training classes?

I’m a dog trainer who’s been mainly focusing on one on one sessions but I’m wanting to start holding donation based group classes for those looking for more affordable training or for people who don’t need private lessons and just want to learn or polish up the basics.

Are there any public spaces that would allow me to reserve a spot for an hour or so a week for free or very cheap? A long time ago I attended some training classes held at middle school or church fields or parking lots, but are there any other options that anyone knows of?

Thanks so much!