For example, sometimes as a GC a person you know will ask you to do a job, you say to yourself, this will be quick and I'll get a little capital for the next deal.

For example for the E 18th property, here is the Income tab.

see, for example, what this guy did.What I learned after 1 year of house hackinglive there for a few years and save up all the money you can. 

For example, I am not really cut out for marketing and sales so I partnered with someone who is 10x better than me at it. 

For example, an agent would collect a reduced commission, flat transaction fee, or no commission if the buyer sources an off-market deal directly.In your case, if you'd like to compensate your agent, you can include it in the loan.

While some leases say they will remove all evidence the sign was there and restore to original condition, I doubt that happens in bankruptcy for example. 

Here is another good example ($10k+ trashout): 

Example: A borrower has a $25,000 student loan balance and you multiple it by 5%, which equals $1,250.

For example, in my building the heating pipes for the second floor apartments probably run 30-40ft before entering those units.

So in your example, buying a trackhoe might grow your business or create greater profit by eliminating some outside costs, or letting you take on bigger projects, or speeding up existing projects, etc (just an example).