I believe in this so strongly that I have even once confronted a large advertising client about this issue when I discovered they had language to this effect in their terms of use in the past, and asked them to change their policy, at risk of material revenue loss to our company.

. - PM has no breakup/termination fee- PM does not take project management fees, except on large or complicated CapEx projects exceeding $5,000. 

For example, to get up-to-date property tax data you would need to scrape every county's tax data website (thousands of different websites, data formats, issues, etc...) then aggregate and clean the data.

I'd break down residential real estate like this (definitely some subjectivity here):A class area= High year-over-year price appreciation, excellent public schools (elementary school ratings are the most correlated to higher real estate prices), little-to-no crime.

The downside is that these types of properties come with high property values, meaning a large mortgage.

In my experience the % booked on each platform largely has to do with the target audience. 

Spent a minute on their website and this in particular stood out to me as a red flag.

I also think the BP books are excellent values.

It was the purchase that jump started my real estate investing career by providing a high consistent cash flow, and a large capital gain 4 years later.

It would take considerable manpower to show every rental and every lead for a large company.