Scott Prock said
1 year, 1 month ago: @pchiappa my guess is you were given a file at 300dpi, even with a dimension of 851×315 depending on what you opened the file with, it could look huge.
@roguecitrus Regarding the original topic … when I created the cover for my business page it took me nearly three hours to complete. I went through a few versions before I settled on what I have now, and I’m the type of designer who has to have every pixel just right. I too charge $99, but I have clients I do white label design for and only charge them $75.
Something else to consider … if a designer is good, and can crank out a quality design really fast that doesn’t mean they should be paid less. How many years of experience does that designer have, how much did they pay for education in order to learn those skills. Someone who becomes more efficient and decreases the amount of time it takes them to do certain jobs has just give themselves a raise without raising prices to their clients. 
Now, if you’re talking about someone grabbing a stock photo and just slapping it up with the correct dimensions, then yes, $99 is too much to pay, but then again, anyone can slap a photo up, so why would they feel the need to pay someone else.
… Scott