I have been doing research on the usual sites (Zillow, Truilia, Realtor, etc) and believe to have a pretty good grasp on the numbers so far. 

I've heard the term used a lot when it comes to estate planning, but maybe I don't grasp it as well as I thought I did.

This site and valuable input from yourself and others have helped me get a grasp on where I want and need to be ...

But it sounds like you have a pretty good grasp on it already.

This will allow you to grasp the basics so that your time with a mentor will be better utilized for more advanced material.Since you didn't mention a particular REI area of interest, I added the below links for your review and selection of one of the three most popular niches or all if you so choose.http://www.biggerpockets.com/renewsblog/2013/02/22/buying-rental-property/ (how to buy a rental property) http://www.biggerpockets.com/renewsblog/2014/01/07/flipping-houses/ (step by step guide to flips)https://www.biggerpockets.com/renewsblog/2015/01/31/ultimate-beginners-guide-real-estate-wholesaling-2/ (Ultimate beginners guide to wholesaling)Now that you have made the move, below are some links that will help with the navigation of the site. http://www.biggerpockets.com/startherehttp://www.biggerpockets.com/meethttps://www.biggerpockets.com/alertsHow to Use @Mentions on BiggerPocketshttps://www.biggerpockets.com/ruleshttps://www.biggerpockets.com/termshttps://www.biggerpockets.com/inviteshttps://www.biggerpockets.com/perkshttps://www.biggerpockets.com/forums/categorieshttps://www.biggerpockets.com/courses/a-beginners-introduction-to-real-estate-investing (video courses)https://www.biggerpockets.com/real-estate-investing (Ultimate beginner's guide to REI)Before your 1st purchase, please ensure you visit the below link for some tips.https://www.biggerpockets.com/renewsblog/2014/12/19/real-estate-investing-success-smart-tips/REI books suggested by BPershttps://www.biggerpockets.com/renewsblog/2015/11/13/7-real-estate-books-beginner-investors/ (7 absolute must read books for beginner REIs)http://www.biggerpockets.com/renewsblog/2013/04/14/best-real-estate-books/?

Once you have a grasp of ALL of the costs involved, values of property, labor, etc. you have to determine how to balance it out so that each partner has the correct percentage of the project in relation to their investment. 

If borrowing from your 401k is a desperation move, or grasping at the idea of something that is not realistic, then you are better off leaving those funds in the 401k.  

I can say this- MANY realtors are not themselves investors and may not fully grasp the mindset of an investor.  

I really have a good grasp of how to invest down there and have solid connections that I trust.

I think you are not grasping the concept of working smarter instead of harder.