Well, this is all matter of opinion. The problem you have, no matter how you slice it, is trying to get someone as excited about your project as you are. My repeated experience has been that you won't be able to find someone like that. And if you do, you then have to convince them to put up money - something you're not even prepared to do yourself. That should make you think about the viability right there. You're not even willing to remortgage your house or max out your credit cards to put into the business. By comparison, in years past, I have done both of those things. But I had the numbers to show that what I was doing wasn't a hope, I had numbers and just needed capital to expand.
>>>Would you (hypothetically speaking) be willing to invest X amount of money and make it grow, if you believed in a project for 50% ownership ?
My personal answer? No. That's why I provided the example in my first post - I've been offered this and declined. Then once they had built a busy website, the ownership deal was off the table.
Perhaps look at this from another perspective. Realistically they have to commit funds + work. In exchange, you're actually offering 50% of nothing. That's harsh, but I think you need to look at this from this type of perspective.
My personal recommendation, FWIW,is to figure out how to do the marketing yourself - and DO the marketing yourself. You will find no one better able to do so anyway. The result of that will be both more money in your pockets, and a more solid business foundation because you know how to do everything in your business.