What kind of return it your money partner looking for? What kind of payback period does he want?
Personally, I think you goals are admirable. I know I started 3 years ago with very little knowledge. Your doing it right by starting on biggerpockets. I wish I had known about this website before I bought my first couple deals.
A 5 year plan that starts with a 100k bank roll is a great place to begin. I also have a 5 year plan, but could only pull 14k out of mt 401k. I leveraged it to buy 3 houses right out of the starting gate. Was it a good idea. Probably not, but I learned a ton and my equity position and cash flow from the three is amazing.
Each path is different & I don't know your area. If things cashflow were you live, my first step would be to use a 5% loan to purchase a cash flowing 4-plex that you can live in and manage yourself. Rent out the other 3 units & rent the extra rooms out in the unit you will be living in. It will give you the experience you will need when you are managing multiple units, allow you to live rent free & allow you to make some extra money. There is also nothing like a home loan to skyrocket you credit score.
In the mean time decide how much you need, to do REI full time and if you can acquire it with the 100k. And also if landlording is for you, because it isn't all Unicorns and Rainbows. If it is, read some of Ben Leybovichs articles on Investing in Multi-Families. Maybe you will decide that Flipping is really what you want to do & you realize that landlording isn't all its cracked up to be.
Just some thoughts