Saving for first rental property and am working on putting together resources in helping along the way.

1. Not far enough along for a GC yet
2. Have eyes set on mortgage help
3. Not far enough along for property management

I'm left with realtor/appraiser.

Is a realtor going to be my best bet on a resource to help determine what reasonable rental rates are?

To me, determining this is the first decision in a go/nogo situation because it drives what your return is/can be.

Are there any realtime resources out there that give rental rates based on size/amenities/neighborhoods etc or are you just kinda winging it and relying on a realtor?

Just check what's on the market for rent on Zillow. If you can get some recent comps from a realtor that'd be helpful too. Make sure to check the pictures to see how yours stacks up. Take professional quality pictures and stage it to look nice. If it's empty make sure it's spotless (paint touch ups included).

ETA: there are other resources and hopefully some others can chime in. I'll check with some Home Vestors connections to see if they have something.

ETA from contact:

We use rentrange.com and rental comps from MLS. Zillow rent zestimate just as another data point since its accuracy is pretty inconsistent.