AC only works intermittently?

[superlaura328]

Hope I'm not duplicating a previously asked question, but I couldn't find one!

I have a 2009 Yaris. The AC only works intermittently. Over the past year or so, it would usually work, but once in a blue moon, it would only blow verrrrry softly... you could feel cold air if you place your hand over the vent, but it wasn't enough air to reach you in the seat. Now, it is not working far more often than it is working (of course, just in time for summer). This happens no matter what speed I have it set to.

Any ideas that might cause this? I am also experiencing the apparently common issue for Yarises when your AC drain tube clogs up and starts leaking into the passenger foot well, although I have been able to resolve that issue by clearing the tube periodically. Are these two things related?

Ugh. I am trying to avoid a visit to the auto shop because I really can't afford it right now, lol. Any ideas you folks have will be appreciated! :)