What is your biggest 'out-sourced' expense, aside from contacting?

[Melissa Thompson]

My husband and I are just getting started on our real estate investment journey. We both are prior-military and have education benefits at our disposal from our time in. (Basically, we have some free schooling) I am looking for some advice on what education we should seek in order to maximize profit. So, that being said, aside from actual contractors doing labor in/around the home, what is your biggest expense? Realtors? Design? Legal aid?

Any input and advice is welcome. Thank you for your time!