I know there are e-commerce kits out there you can grab off the
shelf for cheap ... but if you're looking for backend inventory
management, databases with reports, security, load balancing etc
.... plus hosting, and tech support, you could be looking at 100k
onwards .... some of the more experienced chaps at my place have
worked on banking and transactional systems that runs into 7 or 8
digits ...
unless, of course, you're content with those mom-and-pop
sell-a-trinket sites ... a nice static website you can get for 5-6k
.... but with e-commerce and bells and whistles ? .... hmmmmm ....

but yeah ... it seems like the TS has a case .... but then again,
I'd hesitate to resort to a lawsuit ... the bloodsucke .. sorry,
lawyers, will cost way way more than 6k for sure ... 