It will depend on what you see similar boxes going for on craigslist in your local area. It really varies geographically. Right now, it seems to be raining tool boxes on craigslist too. I had been looking for quite a few months and very few came up that I was interested in. It picked up in December and January has just really taken off. I bought a neat old Mac Tools stack but had a tough time making up my mind which setup to buy with all the choices available. As a con, your bottom cab has few drawers. As a plus, your top and middle chests have a fair amount of capacity because they are full depth, or close to full depth. Most Cman top chests I see listed are only 12" deep. The condition also looks to be quite good and I think yours are probably a decent build year. I could see it going for anywhere from $225 to $350, maybe $375, but again depending on your local market, I could be off. I have seen some smoking good deals lately and they skew buyer's expectations a little. I've seen a couple similar setups listed for $400, but they haven't sold and I wouldn't spend that much on them myself.
Do yourself and your potential buyers a favor. List a good ad. By that I mean, give the dimensions of the boxes W x D x H and state whether you have keys, etc. Your pics are good and illustrate the depth of the top and middle chest. Be sure to point out that those top/middle chests are deeper and your drawers are ball bearing. Personally, for me, the benefit of your top and middle chests are somewhat offset by the fewer drawers on the bottom cab. If you think your local market is too competitive right now, you might wait a few months and see if that changes. Of course, it will be taking up the space if you do.
Good luck with your sale.
That's probably because everyone wants a wider box setup now -- including me! 
