Hello, I am a 21 year old trying to educate myself more on real estate investing and hopefully look into buying my first rental property sometime within the year 2022.  I have listened to many podcasts/books and think I am ready to make my first deal happen.  

My main question I have is, how can you tell if the market you want to buy in tends to rent well for SFH (single family homes)? I see a lot of houses up for rent in my area on all the different listing sites and I am not sure if this is a bad sign or not since I would be competing against a lot of different rental properties for tenants. My fear is that I buy a SFH to rent out and then I can't find anyone who wants to live their and pay me rent.

Follow up question:  I see a lot of articles mention that "the property is located in a B- neighborhood" what does the letter grade of different neighborhoods mean?  And is there a way to calculate that so you know which area you are buying in (A, A-, B+, B, B-, C+...)???  I understand that the grade represents how nice/favorable the neighborhood is, but is that just someone's opinion or is there a way to calculate that?  

Maybe these are silly questions to someone much more experienced, but I would greatly appreciate any advice, metrics to look at, or links to any additional resources that people have found on how to attract and maintain a tenant long term.  So happy I found Bigger Pockets, learning so much already.  Thank you.