I am not an atty and not licensed to practice law.
A single member LLC provides little to no asset protection. Especially if you are personally managing the properties. You will always be personally responsible for your personal actions. You as the property manager didn’t replace the loose board. You will be personally sued. The property owner LLC will also be sued. No entity will remove this liability from you. Ever.
It gets a little better if you are using an unrelated management company. Then the property owner LLC is sued, and the management company is sued, as well as the person at the management company that was negligent. (This is why owning your own corporate management company is false protection. You will still be personally sued for your personal actions, even if you are acting as an agent of the management company.) At least in this scenario, your other assets outside the LLC are protected, ASSUMING that the property is properly owned and titled in the name of the LLC. If you personally purchase the property (as most banks require) and then deed the property to the LLC, things get tricky.
A multi-member LLC is intended to provide protection for a member from liabilities arising from another member’s actions.
example: LLC owns rental. Member A, the town drunk, negligently kills a kid while driving drunk. Member A is sued and the plaintiff wins a judgement against Member A. Charging order protection prevents plaintiff from taking ownership of Member A’s personal property interest in the LLC, and potentially forcing a sale that harms Member B. Thus both the LLC and Member B are shielded from damage caused by Member A’s personal liability outside the LLC.
Same scenario. This time it’s an S-corp. Plaintiff wins judgement. Corporate stocks are considered an "investment " of A, and are awarded to plaintiff to satisfy the judgement. Now Plaintiff actually owns shares of the S-corp that owns the property. If plaintiff now owns a majority interest (or even a significant minority) plaintiff can force a sale, force condemnation, prevent repairs, or a host of other bad news that will have a negative impact on B.
Little different scenario: Member A is property manager and fails to repair the loose board. Betty slips and breaks her neck. Member A is personally sued. All his personal assets (house, car) are at risk. The LLC is also sued, putting the rental property at risk. Member B is a passive investor and was not personally responsible for the accident. Mmber B’s personal assets are protected. He may still lose his part of the rental house, but his home and other personal assets are not at risk. He would receive this same protection from an S-corp or C-corp.
So we see that both a corporation and LLC provide the same protection from liabilities arising from INSIDE the entity, but only the LLC provides protection for a member from liabilities arising OUTSIDE the entity.
So, what are you trying to protect, and from what?