I've been seeing "decent" (good working condition but with some usage wear on decals/paint) black FW's going in the low $200's on eBay. I just got one about a month ago for $202, with a case in really good shape & original pedal, manual & service records. The decals are worn from use but she's a really solid machine & sews beautifully! The only thing she was missing was the tension screw in her bobbin case, which I think cost me about $2 to replace.
Feet & accessories to fit a FW are readily available - Singer low-shank accessories are everywhere.