You snowball plan has a very high success rate.

Top 3 reasons owners hire PMCs:1) No time to manage correctly2) No time to learn how to manage correcly: laws, documents, processes, etc.3) They're too nice and need someone to "save them from themselves"A good PMC can usually earn their fees by better managing the property/tenant than the owner, thereby:1) Increasing owners net profit2) Decreasing owner's time commitment, stress, headaches, etc.No matter what though, you should always plan to commit a couple of hours a month to manage your PMC.

If you set it up well, don't worry, you'll get guests when you repost.If you really want to capture the existing bookings, then go for it and plan to re-furnish it at the start of slow season.

Take a look at what markets you are planning on starting in and make sure it is a growing market where the appreciation is obvious. 

I really wanted to try finding a duplex that i could immediately rent out the lower half rather then buy a SFH and have a higher mortgage overallHow did you find this deal and how did you negotiate it?

I would count on having at least half market rate tenants, in the event Section 8 rents are higher than market, which they are in our market (granted you will need to subtract the utilities from the rent).  

I think I may have just answered my own question, but is it worth it to put only 10% down, and waiting for the equity to build to 20% in like a year and a half, or to bend over backwards, take out a loan and go in with 20% from the start?

did half the flip work, sold with new walls and new electric/plumbing.

I typically plan for 5% of my rents to be saved for vacancy.

Yeah that sounds like a good plan!