I own a firm and we develop solutions for websites to increase their sales. This is mainly done through a/b testing and conversion rate optimization. In 2014 we developed an amazing solution that is just ridiculously successful on every retailer we tried it on. The issue is we are taking this solution to potential clients. These are large companies and they have heard it all before. They want to see what the actual solution is, but if we show them then they can just implement it themselves and say something like "we were planning on that". It is so simple that their developers can set it up in a couple weeks. But, this is our simple idea. This is what we do. We develop ideas that generate a lot of revenue for our clients. Is there a general contract that can protect us so we can show companies exactly how our solution works without them using it unless they pay us our fee? I prefer to find/buy a pre made agreement and modify it. We are just not sure what to look for.
This doesn't exactly answer your question, but I think you'd get something out of watching a video I watched earlier this week. It's called "Mike Monteiro: F*ck You, Pay Me." I can't do links on here yet, but the video is on all the major sites like youtube and vimeo. Should be easy to find. It's more geared at web designers and graphics artists ensuring that they receive compensation for their code/art, but I think it also applies to your situation. The main point in the video that made me think of it after reading your post is that he mentions that a good lawyer makes you money. Making sure you have the right legal assistance ought to save you more than it costs you.