We are setup as an LLC and there are 2 partners (though soon will be just one, and used to be 3
LLC is not a business type, if there were 2 or 3 partners then it was a partnership with a written agreement registered with the state. If the business changes to a single owner - that means the partnership has to file a final income tax return, and close down. Then the remaining person starts a new company as a sole proprietor.
You need, need to get with a tax accountant on this issue.
chart of accounts is a different thing, the chart of accounts IMO should mimic the tax form the company files, and you create sub accounts for detail where you want it.
An account is not what you do, the account records the amount you made or paid for that type of thing. In QB items in the products & services is what you do, and each item links to an account that gets posted to.
QB is not suited for renting.