Don't compromise because it will likely end with you being the helpless landlord in the scenarios you describe.

But some owners of 5-20 are in expansion mode, oftentimes borrowing against other property to buy more units, compromising their reserves, and pushing their comfort zone before they are ready. 

I want this to be a 10-15 year investment of my time and money without compromising my current career....but if I can sustain myself doing this then I would totally quit.My mind is like a sponge right now!

When your ready to address investment choices, write out your goals and pick the property that best meets the INVESTMENT GOALS and don't compromise it with personal living desires for said property.    

They told me it is hard to fill studio apartments unless you compromise your standards on screening.   

The big advantage of buying a condo is the maintenance free nature of it, but if the people responsible for handling the obligation of collecting the money and managing the association are compromised it will have a necessarily negative impact on your investment.  

I compromised by opening the front and back doors and letting them peer into the apt from the hallway (with masks on).

If house #4 seller isn't inclined to compromise with me I do not want to get bullied into buying a house.

In less risky, well appreciating markets, this may still be a good move, but you have to know what compromises you're making when you go in.

I think 75% sounds fair and a good compromise and if he doesn’t take it you now have his address