I'd be very nervous leaving your own equipment in his garage. When he finds out that he can't afford to replace the stuff you own he's going to change his story and claim it was all jointly owned to the judge.
Trying to force you to buy out "his interest in the jointly owned equipment". We know that is not the truth. But you have nothing in paper to prove what you say to the judge.
Time to split the business is now. You take your stuff give him the cash for his half of joint owned stuff and store it in your garage, parent's garage, grandparent's garage.
This guy if given the time to bite you in the ass will not hesitate to do so as soon as he realizes that he is to broke to go and pay for whatever it is that you take away access from him.