Refurb/Reselling questions

So I recently fell into some dozen or so xx20, xx30 and xx40 generation Thinkpads and planning on reselling them. Among them are three W530s. They're all three cosmetic beauts but with the exception of one, there's something wrong with each of them. Like the always on USB2 port on one being broken, one didn't come with the color calibration sensor, only two have the 6300 Centrino-N, things like that.

Here's my question - is it worth swapping out parts and upgrading these machines before selling? (I can get DDR3 DRAM stupid cheap.) As in, build two super W530s out of three and have a redheaded stepchild of a W530 and selling it that way or just sell as is as close to factory spec as can be checked on the build sheet on Lenovo's pcsupport site via serial number lookup?

I might keep one. How would you prioritize which one you kept if this were your choice? Pure proc speed? Other differentiators - network cards, WWAN card, mSATA SSD, broken always on USB2, Color Sensor, 3 different CPUS good/better/best, cosmetic condition, good, better, best.