I appreciate the reply, but Intuit has been in this game a long time. Frankly, I find it baffling that QB in its many forms over the years STILL does not account for (no pun intended) this very basic need that is usable across a wide spectrum of businesses, particularly those businesses that are heavily serviced-based.

I've visited your blog, FAQs and knowledge base on several occasions, as well as many QB-related forums, only to realize I am far from the only person who has pointed out this severe deficiency, and one for which a workaround seems improbable with QB alone. Naturally, being no expert in QBO, I remain open to the possibility that someone with more experience can point me in the right direction. As such I posted questions about this topic in the past, namely, that a QBO Project requires a single Customer association. Those with far more knowledge and experience in QBO than me acknowledge the limitation I described. Therefore, I must conclude this is a real serious deficiency in the application, lacking a key feature from which many of Intuit's QB customers, including me, would surely benefit.