My favorite home gym products: (AFFILIATE DISCLAIMER: Buying these products or anything else from Amazon.com within 24 hours from clicking any of the links below, will support my project financially, even though the price of the product you buy stays the same for you. Meaning you get the product, but also help me create more useful videos in the future, a double win!)

Slantboard: https://amzn.to/3HuKTKk (metal) https://amzn.to/3O9lxVZ (wooden)
Slantboards are good for a bunch of different things, calf stretches, all sorts of angle changing variations of lower body exercises. It's like a thing that you might or might not see why you need before you have it, but once you start using it you find more and more use for it haha.

Massage gun https://amzn.to/3S7gkzc (mini)
Maybe the most important recovery tool that all sports people should have?

Short loop excercise rubber bands: https://amzn.to/3SbxEmE
Useful for a lot of shoulder, hip and other excercises, really easy to bring when travelling or heading to volleyball practice.

Rubber bands: https://amzn.to/3HrnRDM
The low weight ones are really useful for for example stabilization/strengthening exercises for the shoulder. Bigger ones useful for squats that become heavier near the top, and other big muscle group excercises.

Flexible and easy to move in weight vest (possible to even play or drill volleyball in): https://amzn.to/3u4w5Pf (However, I have my doubts toward that the heavier versions of this have as sleek of a design.. But I wouldn't recommend for example doing volleyball drills in any of the heavier ones anyway..!)

Yoga wheel and peanut massage ball https://amzn.to/3vGQTgd

A yoga wheel is also something you might not realize why you need at first (they are great for opening up your chest for example), but over time you will discover more and more uses for it.

Lacrosse massage ball https://amzn.to/3u4Glai
Probably the best recovery tool after the massage gun. Harder than a tennis ball, and also grippier, so it doesn't "slide away" on the floor or wall or whatever you use to put pressure onto your muscles.

Thick yoga mat for comfortable stretching: https://amzn.to/3StVkUo

Kettle gryp: https://amzn.to/3u1thCC (I haven't tried this but would for sure get it if I for some reason had a lot of dumbbells at varying weights at home.)

Deadlift grips (good for long hanging stretching) https://amzn.to/48Ikdla
If you want to take your hanging to the next level (for your shoulders' sake), you might need these to take off some of the strain on your hands and forearms.

Basic kettlebell: https://amzn.to/494syiC
Many uses for this one. I have a 8 kg (17.6 lbs) one that I find very useful to a bunch of stuff.

Yoga blocks: https://amzn.to/3UfPzvb
For individualizing stretches and yoga-poses, so that they fit your body. I'd recommend having at least 2 if you want to work on your mobility a lot, but something like 4-5 blocks could be handy at times.

Yoga belt: https://amzn.to/3HvniZG
Also a tool for making certain stretches easier/more effortless.

Cheap weight vest: https://amzn.to/3SdHaFK
Maybe the cheapest weight vest I have seen.