But neither are the people selling you that you can get rich quick using other people's money i.e.

Would it be best to just keep ALL communication with him from here on out purely in writing?

Continue to communicate with them what they are buying.  

Do not expect riches from the start, especially if this is a turnkey, more often then not it will be retail price and other parties interested in it.

Like Robert Kiyosaki's "Rich dad" buying up parts of Waikiki beach before it became a major tourist attraction.

Whether it's communication skills, market knowledge, or something else entirely, I'm eager to learn how I can best serve investor clients.Additionally, I'm curious about the best ways to connect with investors in my area.

While I've done some research on the topic, I feel that hearing from those with firsthand experience could provide invaluable insights.From what I gather, co-hosting involves assisting Airbnb hosts with various tasks, ranging from guest communication and check-ins to cleaning and maintenance.

Here are a few I recommend: "Rich Dad, Poor Dad" by Roberto Kiyosaki; "Set for Life" by Scott Trench; "The Unofficial Guide to Real Estate Investing" by Spencer; "The BiggerPockets Ultimate Beginners Guide" found here on BP; "The Book on Rental Property Investing" by Brandon Tuner.

(But I've been listening to BP podcasts the last 2 months and read all the Rich Dad, Poor Dad books).  

Since then they have been terrible communicating with me.