There is a lot of ways to skin that cat really depending on your goal.On my personal residence I have a 30 year mortgage but I pay on a 15 year schedule. 

I would want to put skin in the game.

I want tenants to have some skin the game with repairs to cut down on petty repair requests.

But if I could have I would have been investing in smaller (also cheaper - in the sense that they cost under 75K, not cheaper as in run down or beat up) property, primarily duplexes or SFH, because it allows you to gain valuable experience and learning lessons while not necessarily having too much on the line, or "skin in the game" if you will - However, when you move across the country to live in Los Angeles, extra money is kind of hard find the first couple of years - but I made it through and here I am!

Family, friends, doctor, CPA, attorney, neighbor, etc.Another option is hard money lenders, they will be more expensive, require skin in the game, and your experience level will dictate what terms you can get.Lastly, you can find a JV partner (joint venture), one with the cash but less time, partner with him or her and split profits.

Most HML's expect their borrower to have some skin in the game.

The intent of the "down payment" protects their interest in the property, giving them a buffer with your equity,  and shows them that you have "skin in the game."

I'm still green to this and aside from owning my own home now for 13+ years, I'm ready to put some skin in the game.

I would advise someone just starting out to partner with an experienced flipper or contractor who is willing to put some skin in the game (they can pay for the rehab cost or defer their payment until the property is sold or completed in exchange for some equity).

From what I've experienced and what my mentors have advised me of is that if there is no skin in the game, there is nothing to lose and you don't want to be in business with someone who has nothing to lose.