Took HELOC in Oct 2023 for the (2nd rental) to pay off all debts. 

And I’ll know if I am getting ripped off in the future.

I know there are a lot of tax benefits and write offs associated with owning real estate that would be lost as a private lender, but can anyone tell me what to expect?

.· The taxpayer works more than 100 hours in the business during the year, and no other staff works more hours than the taxpayer.Hiring a property management company, therefore, effectively off-loads the primary work from the landlord, allowing for the income generated by the investment to remain passive and lower tax rates than active income.

These checks are after all closing fees and the remaining mortgages were paid off, meaning it's my profit.

I'm glad you're liking it so far, I've run into the same thing with clients where the HELOC sort of throws things off. 

So if you make 10% the first year on $1 of equity (so 1.1x your money), you need to make 10% off the 1.1x starting point (so 1.1*1.1 = 1.21x) to maintain a 10% average CAGR across the two years.In your example, if the $800 per month is after interest, then you made a 38% return (CAGR) for that year ($800*12/$25,000).

Within that time frame the business's revenue has grown significantly and has outran my tax write-offs from buying the company.

As an entrepreneur, there is not such a clean off button. 

I have the opportunity to buy an off market double wide manufactured home for half of market value, but because it was built prior to 1976 I can’t get anyone to lend on it.