Personally I'm not sure that I would ever do it on my own residence, but it doesn't seem like a bad solution for rental properties where every penny is being pinched as @Mark Fries suggested. 

Work hard to get promoted at your job, save/invest more of your income, about enough so that it pinches you. 

That means if you are flipping, make sure that you use a lender that can also refi the property in a pinch...you have to check on the rental refinance loan terms to make sure your DSCR is manageable for the lender; do the math as if you have already taken out the HML and LOC.

Pinch me.Corey

I pinch myself on a regular basis :)

where have you found money for a rehab in a pinch before? 

If you're at a lower price point, people are pinching pennies.. and that's another expense the buyer will have to pay for... definitely black or Stainless Steel,  maybe even check out CL for a used one... same thing for WD... 

Putting down 20% would keep me from being in a pinch and I still have a little of work to do on the property.

Be ready to Front money to pay your contractors as you go and then wait for the bank to penny-pinch over every single expense before giving you your draw.Vitaliy

One of the most rewarding things from a financial, familial and personal standpoint.It took a great amount of time getting prepared both mentally and financially for the endeavor.I do not mind fielding a text from a tenant on occasion, or unclogging a toilet, the day I do I will hire a property manager.I pinch myself daily.