But clearly the owner just doesn't care because nothing has been done about it for a very long time, I really don't understand why.

Securing 100% financing for a project is quite rare because lenders typically want you to have some skin in the game.

I would be careful with a complex that insists you only let them manage the property.

One of them carefully looks through and tinkers with every component.

If you have no skin in the game, you'll usually start at 50% equity and work your way from there depending on what you can offer.But doing 10 deals a year with a partner is much better than doing 1 or 2 deals on your own. just be open and flexible to make a deal that's mutually beneficial

Be careful, wish properly.

So the people with deep enough pockets, that may own thousands of units dont care.

I don't think you can use GoFundMe or Kickstarter to fund real estate investments (but I have never tried), and there are many securities laws you would need to be careful of if you went that route.Basically any asset you have a value is a way to gain access to the downpayment money.That being said, the question comes across that you are very new to real estate, specifically the various ways to finance deals.  

Now that I have a property manager, I heard the %18 and believed that to be the total expense without realizing the additional (cleaning fee, lawn care, state taxes, pool care), etc...so the effective rate is much larger and my net take home much less than I anticipated.

However, thorough research and careful planning are essential.