If your partner is a contractor and wants to keep busy, that could be a different story, but I at least consider looking at long term ownership plans and flipping as very different businesses and a lot to learn on both, so not sure I'd risk losing money and time dealing with flips. 

In other words, there are certain parameters you have to be within when identifying replacements, so if a deal goes south for some reason, after filing the papers that identified that property, you might lose the opportunity to take a 1031 at all.

As is, it looks like the duplex would lose about 10k a year while the fourplex profit about 1k per year...that said Jersey City heights (duplex) is not rent controlled and would appreciate more than downtown Union City.

We have tenants that we have repeatedly put up 7-day curables but we do not want to lose them as a tenant.As for not paying, follow your systems for non-payment just like rent.

Because I’m unable to obtain an insured title for two years, I did not plan to invest in this property until then for risk of losing my investment.

I break even, but i actually lose money on management fees. if I managed it myself I wouldn't be losing money., Lessons learned?

You need to know how to enter the deal and how to exit so you can cover your areas and protect yourself from losing money. 

You're the fish.They often use a mix of fear, threat and urgency to push a target to act.It can be as simple as a 24 hours sale from your favorite shop that requires you to log in to your account first or your boss asking you to wire money right now or he/she/they will lose an important contract that will cost millions.So cybersecurity is important because without that, you might have an incident that can cost a lot of money, impact your reputation and might affect your credit score.

3/1 detached will have maintenance/cap ex in excess of $300/month over the long term in today’s dollars.  

@David Martoyan, the deal you feel you "need" to do is the deal you will likely lose money on.