"Can I just take some good ones and modify them?" I think that's the best approach. Look for similar sites/services or find a few that together do the things y

"Can I just take some good ones and modify them?" I think that's the best approach. Look for similar sites/services or find a few that together do the things you do and copy bits and pieces from their TOS/privacy policy/etc. Depending on what you are doing that is probably good enough until you get some traction. If you take funding down the road I imagine this will all get rewritten for you.