They set up the process as a preliminary ‘interview’ and then if you get the first screener’s ‘recommendation,’ you move on to a 2+-hour ‘interview’ with the ‘director’ to ‘dive deeper and see if you’re a good fit’ because ‘Phil is very selective’—so selective, in fact, that ‘less than 1% of applicants are accepted to join.’

I almost moved to Vegas in 2017, I even interviewed for a job out there, was flown out for the interview, etc. 

Many of the tax professionals on this forum are not "cheap" but can make a good fee for fixing situations where investors relied on poor advice from cheap advisors.My conclusion is to interview a few and go with a professional that you feel comfortable with no only their fee, but also their personality, their experience, their reputation, and their willingness to not only advise you as you start your journey but provide education and planning for what type of investor you want to be. 

Also, check with the property managers and ask if you can interview 2-3 current clients of theirs.

This is a two-way interview, so have a short list of questions to ask the mentor (What books do you recommend I read to gain a better understanding?

interview multiple banks?

This was actually an on market deal that a realtor I interviewed and hired found.

I should have interviewed CPAs directly and targeted those like yourself that match my wealth strategy.

These are probably the agents your sister should reach out to and interview. 

I'd be happy to connect with you to discuss property managers and what to look for when interviewing them.