Our cash flow and other sources of income is modest.  

In this kind of setup you don't normally provide other than starter supplies for consumables.

However, my personal opinion, is that its unethical to mark them up beyond what the consumer would pay normally. 

I'd definitely pay off consumer debt first since you're that close. 

Our income was modest for those years (and still is modest - less than 6 digits last year). 

The quick turnaround aligned with our efficient investment strategy, and the clear profit potential, even if modest, made it appealing.

@Jimmy AlexanderMy first property was a primary residence that I house hacked.Second property was a rental property that needed $8k in repairs.Third property was a flip that made a modest return.

Self-Management:Pros: Saves money, offers control, and builds tenant relationships.Cons: Time-consuming, stressful, and needs expertise.Hiring a Property Manager:Pros: Saves time, provides professional expertise, and market insights.Cons: Costs money, less control, and finding a good manager can be tough.What about you?

. - 1.28 gallon toilets, eco-friendly faucets, eco-friendly shower heads, etc.) as a way of helping this rental property consume significantly less water (enough to save me a few hundred bucks each year...

Also, are you looking to work with investors or more so consumers?