It sounds like you are putting the horse before the card and are more interested in scale than foundation.

Ultimately, my vision is partnering with a private lender so I can spread my funds across multiple deals at once and scale quicker; I'm really happy so far with my agents, contractor, and refi lender, so I feel like getting a great lender would be the next step for me.

If you want to keep using your phone sales method - be HONEST and do not pressure people or "tilt the scale" with words and huge promises like that.

I want the freedom of being my own boss, and completing and finding new deals on my own time, being part of a community and leveraging my network to build a lifelong business that I want to keep learning, and keep scaling and growing.  

I have learned a ton on these forums though I’m posting for the first time.what does not get mentioned enough is that if you want to scale slowly using low money down FHA/conventional loan approach and live in there for 1 year, at a time, you should not write off all the rental income on your most recent tax returns for the existing rental properties.

Even if this deal is too tight, they can  help with administrative tasks on future deals / help you scale your business.  

The reality is you will at some point buy from a wholesaler if you try and scale this business.

Was it due to features, lack of scaling, or something else?

At REI Capital Fund LLC, we’ve worked with a wide range of investors, from those flipping their first property to those building large rental portfolios. One thing we’ve noticed—no two strategies are the same!
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That's the way you scale with less money each time, but you don't want to leave the last home until you have built enough equity to do a cash-out refinance.