Recommendation:
http://astroevanova.deviantart.com/
Pros:
>Very affordable
~$15 for a single character, ~$25 for two characters (with simple colouring). He's also very loose in what he considers an 'additional character' (a shot of a male from the neck down to his knees did
not count as an additional character and was essentially free).
Will even give you a sketch of the scene/pose before asking for payment. Willing to make a lot of changes to that sketch, too. If you don't like how the sketch looks, he'll drop it without issue. You can even request something completely different and he'll go with it. (Please don't selfishly take advantage of this, though I doubt the users here would be likely to do that.)
>Great at drawing hentai
For those of you who enjoy the lewder side of things with your waifu. Doesn't charge any extra for NSFW images, either. (A quick glance at his gallery should tell you NSFW is his forte and probably even his preference).
>Dedicated
Will make any changes you ask for without any sort of complaint. Useful for those of you who are indecisive or bad at noticing minor details you'd like changed.
>Good english
Communication is not a problem. An important detail that can set the mood of the whole commissioning process.
Cons:
>Slow
Works a Monday-to-Friday job and rarely gets the chance to send messages or updates during that time.
>Pricey
Outside of the simple colouring option, he does charge a steep-but-fair price for regular colouring. About $50 for a single character, which really isn't bad at all. This is a non-issue if you go with the simple colouring option, though.