Let's say 3 young single guys want to buy investment triplex.  5 years later your credit is all tied up in that triplex so when one of your partners gets married and has kids and his wife wants to buy a house for the family, they can't do it, because his name is on that investment mortgage. 

I am looking to use a VA loan to get a house but want to purchase a rental property and get started on getting cashflow.

I've done some research and see some suggesting randomly showing up at the house (don't want to do that) or sending a letter/mailer (those things are usually thrown out).

I have opportunities in NC for houses that are all-in around 75-100k, ARV 125K and rent for around $1200.

A minor problem with one house that I'm hoping to rectify this month.

Rents go up, houses appreciate, your indebtedness decreases. 

My girlfriend and I are rehabbing a house and we have work set to begin in the near future.

But these are the people that will buy houses or be long time renters. 

If a house does have some rotten wood ( siding and trim around the windows and or doors , missing an appliance or two ( say there's no stove or dishwasher ) ......

They ended up bankrupt and foreclosed on and I moved somewhere else. 14 years later my lot in a town where building had boomed, housing prices were up about 40% and there was solid population growth had gone from being worth $28,500 to being sold for $19,000.