It is done. I have silenced my inner critic and declared the painting completed. A few lessons learned:

• Request high resolution, high quality photographs if you can't take your own. Even if you don't detail your painting too much, the information from a high quality photo is valuable.
• For two out of three subjects, I used one photo for drawing reference and a different one (or, actually, more than one) for light/shade reference. That is hard, although I am mostly pleased with the results. One good outcome of this method is that the painting doesn't look (I hope!) like a copy of a photograph. A negative side of it is that it definitely takes more time than working from a single photo.
• Speaking of time...It took me longer than I anticipated. Next time, I'll know. Hopefully :)
• The Everyday Matters Yahoo group is a bunch of wonderful people. I am so glad I joined. I requested help with completing this painting and I had very useful critique within hours. Plus the encouragement that every single artist needs so much in order to keep creating art. My husband was very helpful, too, especially since he had the real painting to critique, not the photo of it.

Here is the last photo I took of it. Still a little bit of waviness present. At some point, I just had to make myself stop, put the brush away (speaking of brushes - this all was done with a W&N Cotman synthetic round #14, which is a decent brush, but it made me want to expand my brush arsenal), and let it dry in peace. If I kept working, I'd work it to death.

The clients loved it. I received passionate feedback on Etsy and they promised to tell friends and family about me. Overall, this was fun!