A person doesn't have fur to protect them and thus it can break the skin. 

Beautiful skin, and wavy curly hair. 

This business requires having a thick skin and not getting hung up on minor setbacks.

They want investors to have 'skin in the game'.  

They have zero "skin in the game" right now, so they will just pass off all the responsibility to youHire a professional monthly exterminator and increase their rent to offset the cost to youI would also consider hiring a professional biweekly/monthly cleaning service and increase the rent accordingly

CONS:  You'll already have skin in the game (legal fees, inspection, time) to the tune of several hundred dollars, and if you find some issues and try and retrade with the seller (who, unlike you, has not spent a dime or any of his time) can tell you to go and pound sand.  

It will be difficult for you to purchase an investment property without some skin in the game. 20% would be about standard for an investment property.

Unless this dog is the size of bigfoot with irritable bowel syndrome, I can't imagine how 1-2 days worth of dog crap would be visible from the street enough to make your property look bad.

My question is, how much 'skin in the game' would be needed to lend a first time flipper hard money?

If that's the case you must live their and will sign an affidavit stating such at closing with the lender.They know buyers who are living in a property will fight hard to keep it in tough times which is why you have the better rate and less down than a investor loan.The investor loan they want more down so the investor has skin in the game and it will be painful to walk away when things get tough.