I wouldn't say ozone alone is a proper remediation. You have to find the source of the mold and safely remove it, which can be costly.
That said, I bought a high level (shock treatment level) machine for $400 many years ago. It has saved my arse many times! I use it on questionable stuff, my car, and have also treated whole rooms with great success. It is not certain whether or not it denatures the mycotoxins released from the mold it kills--some say yes, some say no--I just know I feel better after I do it. Also, it cannot penetrate walls and such, so anything you are trying to treat must be exposed.
The caveats are: people, pets and plants must be removed during treatment.
I can breathe it fine for a minute of two when entering/leaving the area, but people with asthma probably want to avoid that.
Since 03 is heavier than 02, it grabs stuff and drops it to the floor and other surfaces. You must vaccuum/wipe down after. I admit I don't always have the energy to do that, but it is best.
I have stayed in the house with it running overnight in another room with the door to that room taped shut with duct tape. Again, don't do this with small children, pets, (especially birds) or people with respiratory issues. I can smell it going in the sealed room, but it doesn't bother me.
You must run it for long enough for your cubic footage, there are charts online I think. I tend to try for at least 8-12 hours for a medium-sized room. It is recommended to not run it for more than 24 hours without giving it a breather in between.
Latex will break down with this level of ozone, and soft rubbery things will get sticky (but not necessarily ruined.) I have destroyed clothing that has elastic threads in it when i forgot to remove them from the closet I was treating.
Bonus: if you have any pests they will flee.
Instructions would come with a good machine, but basically you need to leave a window cracked with a fan nearby, because you need a fresh supply of 02 to make 03. It's a bit of an ordeal, but not that bad, and for me has been totally worth it.
To treat individual items I tape a contractor bag onto the end of the machine .