Certain cap items is fixed or pretty close to fixed whether you are buying a $60K house vs. a $500K house in the same market. 

It’s ran like a business, not a personal investment.Given the heavy workload I have being the CEO/founder of the wealth management company, my wife has set up a well oiled machine on the property management side, due to her perfectionist drive however, it still means that she's constantly dealing with tenants and toilets and replying to items at all hours of the day and night.

By house hacking, you're immediately positioned as a landlord, which will adequately pressure you to learn how to structure your leases, screen applications, collect rental payments, resolve the nuances of managing tenants and addressing property issues, etc.

Creative ApproachesIf the organization is hesitant about a sale, consider proposing creative terms:Seller Financing: The non-profit could retain an income stream from the property by financing the purchase.Partnership or Lease-Purchase Agreement: Offer to lease the property with an option to buy, giving them time to evaluate the relationship.Donation or Support: Consider including a donation or offering support for their mission as part of the deal.

It can strengthen your relationship with your property manager and demonstrate that you value their contributions to your business.It helps ensure compliance with lease agreements.Many lease agreements require landlords to name their property managers as additional insured parties on their insurance policies.

My wife and I have obtained three traditional loans and one lease with the option to purchase, resulting in most banks turning us down based on debt to income (non-portfolio lenders). 

First, what does your lease say about pest/rodent control? 

That didn't help so now I'm looking to charge the late fee and interest as allowed by my lease.

I weigh more on making 3x rent and having great rental history of on time payments with no evictions, no lease violations or violent criminal history.

Investing in NNN lease (Walgreens, Dollar General, etc are your tenants) is also fairly passive, but you maintain a bit more control.