Boy, if this isn't a re-occurring theme? Gas prices?

Single handing pretty much limits you to about 18' in length. Spinnaker equiped single handers; Nacra F17 (not to be confused with some formula classes) or an F16 (which is a true multi-manufacturer formula class). The F17 is a bit thin in the hulls to carry a lot of weight - but if the weight you are putting on board is small then it might fit the bill...there are a good number of them around too. F16 is probably a perfect match for what you are looking for. It's designed to be sailed uni (main and spinnaker only) or two-up with the jib. For a 16 footer, it handles weight pretty well. The F16 is light so it's easier to move around single handed as well. What I'm not certain of, however, is if you can find one used in the states - there are a few of them around but they don't change hands often. New ones aren't that much over $10k though...look up Vector Works Marine (the only US builder of F16)