Specifically, for a seed stage startup. More specifically, one that is a web based platform that uses a freemium business model.
After shepherding 300 equity crowdfunding raises through our platform I'd say all of them have a higher valuation. Reason is it is the entrepreneur that is calling the shots. It is the entrepreneurs offer on their terms on an equity crowdfunding platform.
Once you get outside investors involved shaping the deal the valuation will most certainly go down. Agreed it may then be more realistic as everyone believes their company is more valuable than it is.
My advice? Treat early investors fairly. Money is the lubricant to get your idea into reality. Give them a fair share of the business and they will reinvest when need be.