And that number depends on you, your market, your property and your goals.

I'd be happy to visit about the market.  

Just as bad as the posts you see from time to time of the grandchild wanting to work out creative financing to buy their grandparents house below fair market value.  

Focus on market research by exploring neighborhood rent trends and property values while considering your financing strategy (house hacking, BRRRR, or buy and hold).

Quote from @Marc Zak: In the market where I live (San Diego), appreciation has been strong and many predict it will continue to appreciate in the long term.However, with current interest rates (6% at best) and property tax (2%), the annual cost burden is 8%.Am I correct in saying that appreciation has to be above 8% annually (plus whatever my maintenance and vacancy costs are) for me to make any money in this scenario if the property is cash flow neutral?

I would never let a client purchase in certain areas of my local market....

I am an experienced investor and unexpectely find myself managing a duplex myself and wondering if there is a small landlord (aka inexpensive) simple solution for marketing, background checks and lease creation that markets on zillow? 

Off Market, and KREIA are just a few places to look. 

We do not raise it to market rents, we keep it at lease 10% below to try and reduce turnover.

If they tenant is $300 below market, that's costing you $3,600 a year.