Both have pros and cons.

The BRRRR method is great for beginners and seasons pros alike!

There are pros/cons for both decisions.If you buy, depending on how much cash is needed to put down, may delay the time it takes you to get into rental properties.

It's this: What are the pros and cons of starting out with a partner vs solo?

After analyzing the options it came down to this- to rehab they would need to put around $60k to get a potential profit of $30k (assuming all went according to plan), they don’t want to rent even with a property manager so ultimately, with an understanding of all pros and cons, they want to wholesale.

And, when looking at multifamily, are there any pros or cons on owning the entire complex vs partial? 

I would suggest you learn about the pros and cons of Checkbook Control IRAs before making any permanent decisions.

Since this is your first Real Estate Investment transaction, it will enable you to learn more about Real Estate Transactions and how all the RE Pros work together.With 50% down payment, you will still be very competitive.Goodluck

This is just my opinion of course, and if the deal is good enough, you can weigh the pros and cons, and make your decision.

If so, will you please share pros and cons with me?