It is all dependent on the numbers.If you are planning on putting low money down, the odds of it cash flowing (or even breaking even) in the first year would be difficult. 

For a problem that could have been resolved in a matter of hours/days or just a week at max, you can easily waste a few weeks here; - It is very often difficult to get them to act.

@Kiki Helland Detroit has been the most difficult city to find competent management.

There are a lot of requirements towards the qualified opportunity zone of which you didn't mention the three most difficult parts1) The funding of a qualified opportunity zone needs to be through capital gains.2) There has to be an entity structure of which there is more than 1 owner3) You have to materially rehab the propertyTalk to an accountant to make sure you have all the requirements met.

I am having a hard time finding insurance underwriting for the three-family that I am purchasing:https://www.redfin.com/PA/Pittsburgh/7209-Penn-Ave-15208/hom...The only policy I could get a binder on was from Tapco in...

In your networking/loan terms search I'd reframe your ask, because what you are asking for sounds MORE risky and therefore difficult than another request.

She eventually got arrested and sent to jail right after I kicked her out so suing her for add'l damages above the security deposit amount would be easy to get the judgement but difficult to get paid back.

Partners are difficult to find as well because most people at networking events are either have no experience, looking to remain more passive or way too experienced and have their own dream time.

Coops can be difficult and I understand what you mean when you talk about the appreciation, as I bought a condo in Mott Haven and appreciation has been slower than I hoped (thanks Covid). 

Deciding if it was a borrower's homestead could be difficult.