It does work and keeps from eating into your profit in units under $1500 each.

The HOA has always had financial struggles and a large special assessment could eat up a year or more of cash flow

The only problem you might run into, is a 4' tall above ground pool on sale at Walmart for $100, and you're eating the cost of filling it.

If you get $800-$850/month in rent for the long haul, then I'll gladly eat my words, but that seems high in this market. 

I'm just concerned about eating through too much capital on the down payments and then slowing our growth potential.

So, help me understand why someone who has never bought or sold a home before would think that it’s better to navigate this process on their own than listing it with a real estate agent who eats, breaths and sleeps real estate....?

.," do you mean estimating them as a % of rent or just merely not including them in the analysis and eat-up the cost, ultimately subtracting them from your net income?  

So your COC ROI looks good but you are missing several costs that ultimately will eat-up your current calculated cash flow and put the property in negative cash flow. 

You're more likely to be hit with a vacancy that will eat up any possible profit.

What you're asking for sounds a lot like you want someone to take raw meat & potatoes & serve them to you seasoned & ready to eat, but not cook it.