My parents right now currently own 5 multifamily rental properties and are at the point in their life that they are starting to consider selling them one at a time.

and all while holding down jobs and parenting 5 kids under 5...

Yep these properties are always offered and some unknowledgeable investor will think they are getting  great deal.A few years ago, my son found one of these tax sales properties that was controlled for years by one investor, he forced the cancelation of the tax certificate and offered the city $30,000 for this commercial property, after a few attempts, the city accepted the offer.The property now is worth over $300,000, it has  two large apartments and a store on the first level.Talk to the right people in the city, present your proposal and they may accept it.Good luck.

I also am not a fan of HOA as they have to much control and the rules can be voted and changed at any time.

I graduated high school two years ago and was in your daughter's position, my parents are real estate investors.

I also manage my parents 4 house sour here.

I currently live with my parents and I'm almost 20.I'm asking for anyone to give me some feedback/advice on what i should do.

The fact that the property is being flipped frequently gets caught late in the game by the lender (frequently in a quality control audit just before going to documents) which can burn a lot of you valuable time available under your purchase contract. 

I call it controlling the acquisition.

To control risk, I want to put down at least 20% on my first property.Should I do multiple cash out refinances of my own home for each deal?