Heyyyy everyone

So I'm doing the KLI postal course at the moment, and it's going great, however, I have a quick question... (maybe this thread needs to be in "translation help"?)
How would I go about translating "If you can't sell this than I don't need it"?
I got the first part....
Doch Dangevbe'chugh vaj, but I'm completely stumped with the second part ("I don't need it") since the second part is basically all suffixes (I/it is a verb prefix, "dont" and "need" are suffixes...). Any ideas?
Also, it'd be great if someone could post answers to all the exercises.. I tried sending an email to KLI, but I haven't gotten a response... (though admittedly that was a while ago..)
Thanks
