Hi. I am AKHammonds daughter, and let me start off by saying that I am an underwriter for an insurance company, so I am familiar with all of this, and let me add to that by saying that I can only answer for California, since every state has different laws, regulations, and definitions of "business" and "personal" property. Your policy is the final say in what is covered and what is not: DO NOT RELY ON YOUR AGENT TO KNOW WHAT IS AND IS NOT COVERED. READ YOUR POLICY AND MAKE SURE YOU UNDERSTAND IT.
That being said, your personal property under a homeowners policy is just that- your personal property, not "Business Property", so if you are selling in any respect, the insurance company would have the right to deny coverage. If you are not selling and it is Personal Property, sometimes companies will have coverage for things like machinery and "hobby shop" type stuff, but will have a cap on a limits, like $2500 for machinery but no more than $500 per item or something like that. Sometimes property like machinery is not covered at all- it depends on the carrier. Your best bet is having a homeowners policy and a separate property policy for just that machinery. Most likley you will have to schedule the machinery and equipment and it will be on an actual loss sustained basis, meaning that the insurance company will pay to replace the equipment minus depreciation (versus Replacement Cost, which is the cost to replace the equipment without depreciation- try to go for replacement cost if it is available). The premium for that will be based on the value of the equipment.
If you are selling, you need a Buisiness Owners Policy, or a BOP (which covers your liability as a business and your property). Not a lot of companies are going to be willing to write your business, and if you find one it is going to be a surplus lines carrier, and is not going to be cheap (premium will be based on your annual receipts, subject to a minimum premium, around $1000-$1500, and WILL BE AUDITED by the carrier). My suggestion would be to call an insurance broker, not an agent, and have them look for you. You may have to call several.
Always be honest with your broker or agent: fibbing or omitting can only hurt you- it doesn't hurt the company since they can simply deny coverage because of it, and you are the one left without coverage and out all the premium you have paid.
Good luck. If I find any carriers willing to extend coverage I will post the info.