How thrilled am to own a dozen properties there.

If you are purchasing to sell for appreciation in years, that could be a route to pursue, but is really a gamble.

So unless you want to gamble (and some people intentionally do), you generally want to run a title search and figure out what issues you may need to deal with.You could sell the property to another buyer right after the sale.

She may be thrilled at the opportunity to get some assistance from you. 

that totals 23%  and while you might get there self managing I dont think you will get close to that if you have to have PM manage.. and as others said  location  ( snow rain)  desert makes a difference.. tenant quality ( nice tenant Vs tenant that is rough on house )  I think 40% for self manage gets you in the safe zone if you do better thats wonderful..  50% for fully managed if you do better thats wonderful.. but to cut your numbers razor thin then think U made a bad buy when cost run higher is more on the lines of gambling or wishful thinking.

Your suggestion of having a professional diagnose - a quick google search for exterior leak detection turns up plumbers, who I am less than thrilled with at the moment, obviously.

It’s a gamble.

It is a gamble and some people get lucky.  

Also, many of these investors are funds and buy these in bulk, gambling on the chance (say 1 in 5, as example but not sure what the exact odds are) that it will go to a tax deed sale and they eventually take ownership of the property. 

I know it seems like a gamble or fake money but I'm getting 10% percent returns with no fluctuation.