Sounds like you should talk to an attorney. The ideal would be that you build up your business to the point that you can either simply decline to sign NDAs, be

Sounds like you should talk to an attorney. The ideal would be that you build up your business to the point that you can either simply decline to sign NDAs, because you have plenty of customers who don't ask you to, or at the very least can negotiate very specific NDA terms that won't be a problem for you. But again, to do that, you'll probably need some legal advice. The simplest thing is not to sign them at all.