I have two small start-ups.
The first thing I did at the early stage was to file patents. The more patents you have, the more values you add to your company.
There is a reliable, low-cost Patent filing website: http://www.patentexpress.com/ The services are pretty good.
To see if your idea is patentable, you can watch videos here: http://www.patentexpress.com/browse/video.aspx?cid=9
Good luck!