My biggest fear is that if I ever were to quit my job, I would no longer be able to invest in more real estate (not sure if I would qualify for loans as easily). 

Ones of the biggest was that we had to completely replace all the old electric, luckily we were able to save in other areas of our budget to offset most of the costs but not all of them.

One of the biggest red flags I have as a lender (who lends my own money as well as secondary market loan) is when a rookie tells me there goal is to buy 10, 20, whatever properties in the next year. my next question is how many do you own currently?

My biggest tip here is work with the smaller companies.

The biggest factor to consider is the new interest rate since it’ll likely be higher than your current 3.2%.

Depending on the lender and program your biggest hurdles might be credit score and income and time in job. 

Rent out to roommates so I employ the "rent by the room" essentially.Pros:insane cash flowif your room offer is much better value than other places to live, tenants will stay awhilea small community can be built when your tenants become friends with eachothernever ending supply of tenants (at least in my area)Cons:CAN BE management intensiveWILL BE management intensive until you gain experience and know how to manageIf you employ this strategy, the BIGGEST risk/liability mitigator is being VERY clear from the start about your expectations and that you will evict if new tenant doesn't follow your rules.With my setup - I furnish the rooms and have all utilities covered. 

And you have the biggest mastermind of all in BP.. 

The agent will have access to the biggest platform to get the property sold though, the MLS, so forgoing even a cut rate agent will create more of a loss than the agent fees themselves. 

One of the Biggest Challenges I see for All Real Estate Investing Education Companies out there are Students not being able to take action which resorts to blame and failure.