7) What tips or advice would you give to someone cold calling for the first time?

Also as noted above, some markets being saturated. 

It sounds like you already have a great foundation with your rental and BRRR experience in the UK, and you'll find many similarities in the US market but also a few key differences.For location, I’d suggest looking into markets with strong population growth, economic stability, and landlord-friendly regulations.

In today's market, HELOC rates could be a dealbreaker on trying to do that so be sure to look through all your options first. 

What can I do to get more information on the Canadian markets?

I'm currently working on a few commercial deals off-market including a 35 unit office building. 

Off market from a realtor attempting to gain a listing from one of my available rentals.

It is listed for low 40’s has been on the market over a year, went to auction and didn’t even sell I think we could get it for less.  

Hello REI community,
I have questions in the topic of large multifamily apartment complexes generally around the U.S. Who do you know is willing to answer?
Thank you for reading this far;
     -Ruben

It doesn't sound so much like a scam to me as marketing gimmick to get business.