I want to make my project open source but some of its more advanced features are targeted to companies so I would like to require a donation before I send the source code to the donating company.
It will be something like that: "If you want to use the extended features of XXXXXXX, please make a donation of $499 and you will receive the source code and the jar with the extended features. You will also receive personalized support by email."
Is it legal and acceptable to do something like that? Can the companies donate an amount like that to an open source project? I mean, is it easy for them in terms of their accounting, tax, etc. to donate $499 dollars to an open source project. I know it is not a matter whether they will have money or not but more of a paying procedure matter.