Estimating ARV: need an agent? get a RE license?

[Kim Forgione]

I'm learning about the BRRRR method before I jump in and understand the importance of estimating repair cost and ARV. I plan on buying J. Scott's rehab book soon and hopefully that will help with the former. I heard that I should use an agent to get comps to estimate ARV. But if I buy off market or from wholesalers, why would an agent spend time helping me if he won't make money? I know some may help in order to build a relationship, but if I'm analyzing a ton of deals for every one that I take action on, that would be a lot of work they'd be doing for free. How do investors typically go about estimating ARV? Could I pay the agent a fee for their time? Would it be worth getting a RE license myself? TIA :)