The biggest thing to consider is: if you sell your house, will you also live in the next one?

I like Columbus Ohio because I see it being one of the biggest metropolitan cities in the next 10-20 years, all signs are pointing here!

The neighbor might be the biggest burglar in the town for all I know.

My biggest regret is not signing up to get locked into 20% off annually.

The biggest red flag is that the potential tenant isn't even good at potential fraud.Do a thorough background check to make sure they're not just giving you some nonsense or friends to pretend they're employed. 

Downside is if you have more than a month in vacancy you lose that income and it will take time to recover that loss. 

My biggest issue with snowballing is my family's budget must be paid by a decent percentage of the income I make

My biggest advice would be to take your time and do as much research as possible.

I should also mention that despite owning multiple properties with very little leverage on them, real estate isn't my biggest holding.  

^^^Biggest driver of wealth in real estate is the long-term appreciation, especially in Denver.