QB Issue Resolution:

The prevaling rhetoric on the net is one LLC per property, which per the IRS means one accounting file for each, so yes in QBO that is one subscription per company.  You can get by with essentials if it is one property per llc.

desktop is one purchase price and as many companies as you wish (as your hard drive will hold).

He needs to consult with a couple of business lawyers as to whether or not multiple llc’s is the way to go.

If all the rentals are kept in one company, then QBO Plus is needed, only one subscription though.

a single subscription to QBO is 3-4 times as expensive as desktop over the 3 year support life of desktop, see this comparison, the cost is toward the bottom of the article.  a non partisan comparison of QBO vs QB desktop

Resolution for Issue 'Best way to set up multiple rental properties?' available: Yes (Solved).
Source: Intuit Community forum.

Best way to set up multiple rental properties?: this issue or error code is a known issue in Quickbooks Online (QBO) and/or Quickbooks. Support for this issue is available either by self-service or paid support options. Experts are available to resolve your Quickbooks issue to ensure minimal downtime and continue running your business. First try to resolve the issue yourself by looking for a resolution described below. If it is a complex issue or you are unable to solve the issue, you may contact us by clicking here or by using other support options.

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