@Wei Peng welcome to the site.There is no 1 right or wrong answer to your question.You described several ways of investing that if executed property would all make money & if executed poorly would all loose money.For me personally I look to keep everthing in 1 area to develop economies of scale.

I would then go outside and scan the outside just to double check your findings and make sure you don not have excessive heat loss through the attic etc.Let us know what your find, or even better, post some pictures of the images along with your findings.

The reasoning is in building a strong foundation before giving away his excess, but once the herd is built up to 15 and gives away 5, he still has enough to continue growing. 

That's all they can loose.

It has an old coal room that has crumbling paint and some of the walls have loose rocks/mortar.  

Its our western idea of excess tthat's the fad, and the younger post baby boomer generations are learning that.

Terri, I don’t think the strategy of emphasizing the increase in tax revenue will get any traction as Mecklenburg County has over 350,000 parcels that are surely valued in excess of several billion dollars. 

Well your not going to want to hear this, but if your breaking even on the cost of ownership, your loosing money.

Remind him that filing a false lien is a third degree felony and if he chooses to continue on this route he may be looking at loosing his license.  

Without it,  it is a good way to loose a friendship.Welcome to BP-