A crime bond and additional insured language I've never had to carry before

The distinction you read about is real, and it's the one that decides your licensing question. Managing property for someone else, for a fee, is a licensed activity in most states, usually under the real estate broker license, and a handful of states have a separate property management license. Many of those states carve out an exemption for a salaried employee of the owner working at that one property. So an onsite manager on the owner's payroll may be exempt while your company collecting a 2.5 percent fee across their portfolio is not. Which of those applies to you depends on your state's statute, so confirm it with your state's real estate commission or a licensed attorney there before you restructure anything.

On the insurance, the two you don't have yet: a fidelity or crime bond covers theft of the owner's money by your employees, and the limit is usually set against the largest amount of their cash you hold at one time, so on a 320-unit property think about one month's collections plus the reserve balance. Professional liability, sometimes called errors and omissions, covers claims that you managed badly, a wrongful eviction claim being the common example. Both are typically low four figures a year at these limits for a small firm, but pricing moves with your claims history and payroll, so get a quote from a commercial broker rather than working from a number on a forum.

The part that catches small managers taking their first institutional account is reporting, not insurance. These owners expect a monthly package on their calendar, on their chart of accounts, with variance explanations against a budget you didn't write. That's usually a staffing cost, and it belongs in the fee you quote them.