Work copyrights
It is another sensual question. Theoretically, if you post a project as a webmaster, you expect the job done to be yours. But... not so easy. There are some things you should known.
There are quite lots of freelancers that frequently just sells some stolen/nulled scripts, frequently downloaded from various warez sites. It is especially important, if you post project about some site "clone". (Please read about clones, too. There are some things you should know.) Such freelancers either searches for the web for such scripts, and sells to you. Do you think you get a legal work? .N o of course. So while you post your project, mention hat you want absolutely unique work to be done. Also you should mention that the job you receive cannot be sold to other webmaster. Alas, but this also happens. For a freelancer it is the easiest way to get money. It's ok to do that as long as it's ok to YOU.
One of the way to prevent that is to select a reliable freelancer. For serious projects you should select freelancers with at least several good reviews. Also explore what projects freelancer worked on.
You can also do some pre-check about software origin. Open several files, and read them. If you see something like /* nulled by */ software is 100% stolen.
Browse or search more articles for more information, as I don't see a chance to write everything I know into one article.
