Sorry for bumping...just my experience...

You can make your own chalkboard paint by mixing non-sanded tile grout in with the paint. We did this inside my kids' playhouse. You can mix it with any color you want. I guess the drawback is, you'd be brushing it on, instead of spraying it.

My wife found this on Martha Stewart .com:

Start with flat-finish latex paint in any shade.

1. Pour 1 cup of paint into a container. Add 2 tablespoons of unsanded tile grout. Mix with a paint stirrer, carefully breaking up clumps.

2. Apply paint with a roller or a sponge paintbrush to a primed or painted surface. Work in small sections, going over the same spot several times to ensure full, even coverage. Let dry.

3. Smooth area with 150-grit sandpaper, and wipe off dust.

4. To condition: Rub the side of a piece of chalk over entire surface. Wipe away residue with a barely damp sponge.

I also did a wall with magnetic paint like this https://besttoolexpert.com/chalkboard-paint/ in my son's bedroom. It is very magnetic but it needed 3 or 4 coats and it is very difficult to apply as it has metallic particles in it. We did magnetic poetry on it and he could put up photographs, school notices etc. It would have taken a bigger poster but would nave needed lots of magnets. It is hard to get the surface level becaue of the particles going clumpy but after lots of perseverence and 3 x as much paint as I thought would be involved it was sucessful.