And "decent" multifamily properties are trading at cap rates below prevailing interest rates in most areas (not a normal phenomenon) and thereby are reducing the overall return of the deal. 

Trade off is a higher rate though, so your cash flow would decrease. 

Many people don't make a profit, obviously odds of success get better with experience/good team, etc.consider until you have more time to commit to instead look at buying publicly traded equity REITs, not mortgage REITS, they are trickyget subscription to Seeking Alpha and follow Brad Thomas, Jussi Askola and many others research/writing to start withREITS have beaten the SP500 last 50 yrs, by a lot, 13% to 11% just in last 20 yrs too, and they have taken a temporary beating due to sudden rise in 10 yr rates and hence CAP rates, but their underlying rent roles have only gone up.

Im a GC... but I got my start by working in various trades for free...

Many reputable general contractors have experience with city/township inspections and final inspections before you can sell your home; they can provide value based on experience with trades inspectors and providing more accurate estimates for project costs based on current market value of work per trade. 

Will be using a GC for the new build, but after doing 6 flips in Cleveland and running into bottlenecks of how much the GC can handle, I'm wondering if just subbing out each trade would be quicker and cheaper than waiting on GC's who are overbooked and managing over a dozen projects at a time to finish out my own projects. 

The Sold properties will show you what these deals are actually trading for.In addition to this, since you're interested in multi-family properties, you'll also want to look up recently Rented apartments on these sites.

Brought up by a father who owned his own construction business my entire life, I know the trade well.

I am a newbie who is beginning his RE journey and learning the ropes and tricks of the trade at the same time. 

@Jay Hinrichs Lots of publicly traded builders put homes right on landfills.