They were a dollar off, so I think altogether they ended up being less than $10. Then, I used some black paint I already had and painted them with a craft sponge. If you had spray paint, I would recommend going that route just because holding the letters gets tricky when you are trying to paint them and more and more of the surface area is wet paint. Also, spray paint gets in the crevices better, which would have been helpful in painting the A. But, since I already had the black paint and I am trying to use what I have, I skipped the spray paint. I ended up doing three full coats and then one touch-up coat where I just painted random spots that needed it. Let's say your letter dries to the paper underneath and leaves a little chip but you don't want to re-paint since you're moving on to the next step? Just use a Sharpie marker to color it in. The next step will take care of any difference in finish between the paint and the marker.
Then I purchased this stuff at the craft store:
I wanted my letters to be shiny, so I did three coats of this. This was less than $4, if I'm remembering correctly. And that was it. You can see the finished product on my kitchen wall. So easy, right? I look forward to using this spray stuff for projects in the future...I'm not sure what yet, but I'll keep you posted!