I financed this deal on a 30yr conventional loan and I put 11,000 down with a 6.625% interest rate.

It worked out fine, though each time I got a little less than advertised interest rate (about 9% vs 10%) and I had to send a reminder email to to get my money back, but I did get it back.I ask about others' experience, because I'm still not 100% sure it's not a ponzi. 

At any rate it is possible, but depending on your appraisal it could be a gamble

I do not care what the source of the return is  Historically the highest return is via a value add and appreciation and is more so recently due to the recent rate increase versus earlier this century (before 2022).However, most new RE investors cannot handle extended periods of large negative cash flow.  

Especially in a high interest rate environment where cash flows on long term rentals are muted and there is significant capital required to purchase and list on airbnb.I live near NYC but would invest out of state in an airbnb / landlord friendly state.

You should be able to get up to 80% LTV on a rate term refinance.

If I leave this amount in Sch-E, I get taxed at ordinary income tax rate at Federal and State level, which along with my regular W2 income can be substantial.

I expressed my objection to the rate.

With mortgage rates close to 7% and generally soft homebuying sentiment, strength in existing home sales is unlikely to be sustained," said Alice Zheng, an economist at Citigroup.

Mortgage rates have kept increasing as well, that's why I put a range on negative cash flow.