I can tell you this... the biggest factor making things difficult today are interest rates. 

But also, yes, house hacking is probably going to make the biggest difference in your life in the short term if you have a decent w2.

HOA prices and restrictions is probably the next biggest thing to pay attention to as they will have a lot of influence on your profit margin and growth potential.

Today Buyers will need to be more savvy which they should be making the biggest investment in their life.They can source online information but realize now when they go shopping they are gonna have to pay for it out of pocket.This will 100% reduce the number of agents out there which is not a bad thing, and it will be very good for those agents who are good at what they do.

The biggest players keep the wheels turning by deal volume and keeping people busy.

I believe the biggest arguments against Portsmouth are the high local taxes and of course the crime.

Or, a charging order may be granted.If you're going the umbrella insurance route, perhaps see if it will cover you for several things including just the routine slip and fall (like mold or earthquake).

The biggest value add for BRRRs are Bathrooms and kitchens. 

YES, we may be a little biased, but check out our blog here on BP comparing Detroit to other cities and Deep Dives on Metro Detroit cities & neighborhoods: https://www.biggerpockets.com/...Your biggest question shouldn't be WHERE to invest, but HOW you will invest!

As far as it predicting high on revenue, that's obviously the biggest risk and I'd be concerned about that as well when getting into a new market as a short term rental investor.