Whatever numbers you have in your valuation I need to know how you got them to decide if it makes sense.
(Edit: You may be from the UK, so it's a little different than US. I was speaking for the US case here.)
But I realize that your point is that you'd prefer due diligence and transparency on terms before using a site like WeFunder. The thing is, most investments at that stage don't have that much due diligence beyond market size, team, and traction. I think this is where you're misunderstanding.
I am a YC W13 founder and I just raised a 'seed' round. Our investors signed the paperwork as a 'seed' round. We raised >$500k.
- how much money they want to raise. Say $500k.
- how much equity they're prepared to give up. Say 10%.
--> and there you have it. $5m valuation!
There are also enough quality investors out there who use signals other than hand-wavy financial reports that you could be spending your time to get.