Is it worth it to grade newer keys if you can tell they won't likely get above a 9? 0

[RyanIver]

New to this- 

I normally buy small collections and resell them at trade shows for a buck or two each. Every once in a while I come accross a key issue, but they typically were found in a stack of comics that weren't bagged/boarded, etc, might have some wearing on the edges. Should I just sell as is or invest in grading? Also, Silver age comics taht have seen better days, are those worth grading if they are going to come back at a 2-4?

[ExNihilo]

Calculate the profit/loss based on how much a raw issue sells for vs a slabbed one with the estimated grade.  Factor in the costs of shipping (to/from), grading, pressing, other overhead fees, etc.  Don't forget to factor in the time value of money and any other opportunity costs.

[theCapraAegagrus]

What's "newer"? 21st century?

Probably not.

[comicginger1789]

It all depends on the book.