Having been in the lending space for a while now,  Interest income is not passive - its considered/taxed as ordinary income- just like interest you receive from your bank and savings account.Regarding profit and expenses from a flip, "that depends" on many factors but again if its short term capital gains, its not tax friendly.As always consult with your tax advisor / CPA. 

The overall gain on the sale of the original property was over $500K, and I received $500K in cash.

If he is just a seller, I’d just tell him to stick their property up their net assets.I wonder if he would just disclose his numbers and accounts if I say… you hold the bricks but I hold the access to the $$

But if you want flexibility and quicker access to cash in the future, HELOC may be more suitable.Yes, you could do either option again later if your property builds more equity!

Looking to have access to MLS for investing purpose.

Am I subject to any tax or capital gains tax on that 100k?

Short term capital gains for our bracket would be 20%.

Would love to buy you a coffee or anything to gain some first hand experience from you if you have time!

Since the platform has direct access to your financial data, it can prequalify you for loans, streamlining the process when you’re ready to expand or refinance your portfolio.

This gives you more flexibility while building equity and gaining experience.Risk Spread: More units mean a lower risk of vacancy impacting your overall revenue.