We have a -10% correction in the most vibrant part of US here since fall last year.

Your tenant sounds like he/she is going to be a habitual complainer and never be satisfied.

Also a minor point re: 20 days: my understanding is that the 5 day demand letter can be sent after 15 days of lateness, which many people interpret to be the 16th, but depending on how you read the law, you're safer with the 17th and that's what I've always used.I also believe that if the tenants are habitually late, and you warn them repeatedly that they're violating the terms of the lease, you may be able to evict them for "reasons other than non-payment of rent" (which is a slightly slower type of eviction often used for things like repeatedly disturbing neighbors).You'd also want to be careful not to let them basically change the due date by always paying late, thus establishing (by repeated practice and your not informing them of lateness) a later due date by practice.But these are nuanced issues, not really germane to your current situation but something to keep in mind for the future and when discussing evictions with an attorney or other experienced RE investors.

At the same time, it can lead you to build a perception of someone who might have posted habitually during those college days but hasn't used social media in recent years.I think reaching out via social media to find tenant leads is one thing, but using it as a method of screening, while it can have some benefits, can be misleading/can lead to incorrect info vetting; with social media profiles who's to say whether an account is run by the individual that the page purports to belong to?

Once you complete a few deals, the process will become habitual, and you can look at wholesaling larger pools of properties.

@amy thatcher @Amy Thatcher it's very difficult to not have compassion and empathy for tenants with issues, but they have a way of becoming habitual.

It has a vibrant demographic, that are into recreation, fitness, etc. 

Wall Street Journal: DFW Housing Market Cooling November 27, 2018PLANO (Wall Street Journal) – "Dallas' once-vibrant housing market is sputtering," reports today's edition of the Wall Street Journal.

The midtown section has a lot of craft restaurants, breweries, and vibrant arts scene. 

This seems like an unfortunate set of circumstances (act of God) that has led to late rent, not a tenant who is habitually late and that you fear will start making a habit of this.