If you operate in a state in which by assigning contracts you are considered to be an intermediary and not a principal, then being a licensed real estate agent in that state is a large disadvantage when wholesaling (as defined by simultaneous close or contract assignment).  

I would ride my bike beside her as we talked about how our business would run, how we would treat our employees, and how we would use some profits to help the disadvantaged. 20 years later, the dream is still alive!

As an llc, the money is just going to pass through to you as salary and the llc will pay the companies the other half of the fica taxes instead of you for the same net.Even if you apply the commission as a credit, you will still be 1099ed and owe the taxes.Flat rate broker would save you the split on the commission, but there are some disadvantages to flat rate brokers as well.

Are there any advantages to doing this (if it's even possible) / are there any disadvantages?

Both have their advantages and disadvantages. 

You also much have elected to group the rentals to qualify and there can be disadvantages to that as well. 

I'll start off by saying I'm a 19 year old female who often gets mistaken for a 14 year old female, so I'm not sure if my age/appearance would be a disadvantage.

If you don't know their rules you will be at a disadvantage…just like you were as a kid playing a game on the field, then along comes another kid and changes the rules.To banks or investor group, credibility, is first and foremost.

Is a LLC IRA a better choice for me, and what benefits or disadvantages will it be for me?

Why start out at a disadvantage by having the front unfinished?