I invest in Boise, ID and do quite a few BRRRRs, LTRs and STRs- varying degrees of success depending on how much equity we can force and the type of back end financing we can find, but the tax benefits are great and it's a rapidly growing market and Idaho is probably the most landlord friendly state in the nation. 

Together, the property nets us roughly $1,400/month after expenses.Equity Split: My partner owns 60%, and I own 40%.I'm exploring ways to take out my equity without disrupting this deal, as I feel this isn't the best financial decision for me right now.

*Aggressively paid down debt, focusing on loans with the highest interest rates and lowest balances that could be paid off the quickest, converting debt to cash flow.

But because it is built before 1960 banks do not insure it as it is(not renovated) for earthquake so they do not grant me a loan even though my payslip is quite good 

Make sure to provide clear disclosures to the seller about the risks involved, especially regarding the existing mortgage staying in their name.Insurance Considerations – You’ll need to work with an insurance agent who understands sub-to deals, as the lender might require a policy that keeps the seller as the named insured.Due-On-Sale Clause – While banks rarely call loans due, it’s still a possibility.

It sounds like she's been renting, so there is no equity in her home. 

If you would like to hold the property for longer, that is fine as well, just note that your loan payment will be done after 20 years.

I got the loan.

Right now, the best offers around me are for some 1.3-4 million, that only generated around 100k per year gross, so there would be a high chance of not cash flowing, and paying money, especially with a commercial loan (these buildings have more than 4 units).I was thinking that although the rental itself does not generate money, I would be able to deduct the mortgage interest, and depreciation from my personal w2 income and would be net positive.

Is it not so much the fee for filing that makes it prohibitive but that the equity offered rules out the viability of being a GP in a registered security this way?