So this investment isn't at a valuation and the valuation is only decided at a future round at which point this converts into an amount of equity based off that valuation? I've read about convertible notes before just a little confusing at first.
Right. $150,000 paid in advance. Whenever the company raises its first significant money (usually >=$1M) that $150,000 buys equity at the same rate the new investors are paying.
For instance:
1. I get $150K in convertible debt from Yuri.
2. At the end of YC, my rich friend Joe decides to invest a million dollars in my company at a valuation of five hundred trillion dollars. Yuri thus gets an insanely small slice of my company.
3. Two days later, my company buys Joe's shares back for a million dolars.
4. Now my company goes off to seek actual funding at a sane valuation. Yuri gets annoyed.