Is it about having the know-how to REACT, or can things be done to always be ahead of the curve and PROACTIVELY know when to hold vs sell?

As long as you react fast and cancel one of them  (the second ), then it's not a real issue.

The effect of this is that for buy and hold, it is harder to find properties that provide a return that is better than more passive returns.Real estate prices always are slow to react to market conditions. 

I am currently 20 years old and a Wisconsin native and am simply looking to expand my knowledge and network by working with other investors/agents.

We almost reacted emotionally and started self challenging our analysis.

Just analyze the property, make your offer based on it being a deal for you, either they say no or yes, react accordingly, and move onto the next one.Addressing your 3 concepts:1 - No. 

Deal analysis tools are a dime a dozen, you can use spreadsheets, web apps, native mobile apps, etc, it all depends on your preference.There are a bunch of Excel spreadsheet templates in the BP fileplace for analyzing rental deals or rehabs.Here's a few:https://www.biggerpockets.com/files/user/JasonScott/file/20-sfh-rental-analysishttps://www.biggerpockets.com/files/user/brandonatbp/file/brandon-turners-spreadsheet---rental-flip-hybrid-calculatorOtherwise, BP has their own Calculators you can use to analyze rentals or flips.https://www.biggerpockets.com/buy-and-hold-calculatorhttps://www.biggerpockets.com/flip-analysisWhat type of deals are you trying to analyze?

I have a lot of experience as a handyman from my native Trinidad and Tobago.

I'm a Spartanburg native and have been involved in 100s of deals here since the early 90s.

FSBO sellers frequently make this mistake and then react badly to buyers who have brokers.