Simple e-book covers for the budget minded people. (Could use some advise)

In 2008 I started on my first novel and it took me about two years to finish. I needed an e-book cover and lacked the cash to hire someone to make one. I had no idea how to make a cover myself, however it didn't stop me from trying, and the very first one I made was terrible. I think I used paint to make it. It was really, really horrendous, so I deleted it from the physical plane but it's still etched in my retina. Not long after that horror I discovered Gimp. I played around with it and finally after some trail and error and with the help from online tutorials I made this book cover:

Since then I pulled the novel, because it was a grammatical mess (even after a paid edit), and this year I rewrote the story and got it edited. I changed the cover into this:

I like to keep my book covers simple and often take my time to get it the way I want it. Though I have made book covers in less than 30 minutes, like the one bellow.

Others take more time to complete, because I make more than one version and sometimes I make an additional separate version for the physical book. Like bellow for my upcoming short story collection.

E-book:

Print Book:

I'm thinking about designing book covers for other writers. My target audience are those who need an affordable, simple custom made cover, and who are in need of a quick turnaround. However I'm not so sure about how much to ask for, being I don't want to ask too much because I'm far from a pro, but I can't ask too little because I'm not a novice either.

What I offer:

Custom made e-book cover. (Photo retouching/Editing)
Turnaround of within a week.
Low price. (Probably $25)
Major revising for additional cost.
Final file will be in Jpeg or converted in PDF. (In whatever desired resolutions)

What I need:

The client needs to provide their own stock photos.
Payment in advance and through PAYPAL.


Do you think $25 would to be a great price? Is asking $25 for a major revision too much? Or would it be better also to ask $50 for the book cover including two revision options?

I can also make print book covers, however it requires much more work. (Front, Back, and Spine) Should I also be offering this? And at which price would it be acceptable? Would $75 for the book cover with an additional $50 for two revisions be a good price?

I can only do a limited amount of covers each week, being I've got a day job, and I'm writing short stories in between, and coming November I'll be participating in Nanowrimo. I think two covers a week would be a doable limit.

I'm looking forward to what your guys have to say. :D

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UPDATE

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Made a book sample book cover. I tried my hand at Romance. Later today I'll try to post more.

Gotz another one