I am looking to connect and learn. 

This works if you are connected to the person, or if he/she has commented on the forum..Brandon is tagged, above, and should be able to get you where you need to go...

If you are working your local market, there are other methods of finding leads that are more effective than cards or letters . . . see what is working in your area from REIG members.

But does anyone have additional thoughts on how I can connect with these potential sellers, especially multifamily property owners?

I am an attentive listener and would love to connect with fellow beginners or anyone interested in discussing their experiences. 

I’m happy to connect and help you make any decisions for a specific property you’re considering for this strategy.

Happy to connect on any lending questions!

Better to make connections on here or a local real estate group. 

It's great to have you here.Here are some recommendations for you:Find and connect with other BP members that are in your area: http://www.biggerpockets.com/m...Set up keyword alerts to be notified of the topics that interest you: http://www.biggerpockets.com/a...Read Beginner’s Guide: http://www.biggerpockets.com/r...Check out BP Money Podcast: https://www.biggerpockets.com/..Wishing you the best

You should reach out to connect to members of that group (you can look up NOCO mustachians on meetup.com) to find some mentors that have lots of experience and can give you some guidance.