I have had only one problem:
The needle that forces water into the K cup got coffee grounds in it and got stopped up, but after just running some water through without a K cup it flushed that out.
I recommend after brewing to just remove the K cup and flush a little water through to keep it clean.
As of this writing, they are $53.99 shipped free with Prime at Amazon. I think that's the cheapest Keurig you're going to get!
If you're looking for cheap K-Cups, check out Jammin Butter. Weird name, cheap prices. Last deal I saw was Gevalia for around 30 cents each.