How can multiple people work on one project simontaniously?

Me and a few people are trying to start developing games and I need to know if there is a way to have multiple people work on one project at the same time.

If you have the pro version you can set up a server where the project is stored. If you have have have the basic version it is possible to share project folders but all the settings, scripts and materials have to be assigned in the editor. If you have a big project this a huge work.

Use Dropbox.