Anything he can't do he will charge me book cost for his specialists labor, and cost for materials. 

Have one Bank account and credit card for your rental activities.Get an accounting software to help you organize your income and expenses.save your receipts in an online storage platform such as dropbox or google drive.Do your books once a month or if you don't have much transactions, maybe once every 3 months.Best of luck!

The one thing that I went to because the more time you have getting another property, doing repair requests and all the other stuff that comes with land lording I gave it to a book keeper.

What information was available was in PRINTED form; the local MLS put out a book updated MONTHLY that contained listings, with no pictures, no hard information, just the listing brokers description of the property and the asking price.

Their website says their platform is completely free. Has anyone used it before? How do you like it?

Yes, you can buy in an SDIRA or a SD401K however, having the mortgage in your name is a prohibited transaction. 

I'm just getting into Baselane, but my understanding is they also offer an option to "split transaction amongst properties or units" and have "separate collaborator logins."

Have I raised capital/syndicated transactions large enough to purchase a 50-unit apartment building anywhere in the US?

Just be sure to avoid prohibited transactions, no personal use of the property, and don’t pay for repairs out of pocket. 

I recently got my real estate license and have a good relationship with a broker who will sponsor my license, so I'm not worried about the real estate transaction piece of it.