not sure if our website would be considered a "startup" since all 3 partners are doing it part time but we all invested around $5000 over a span of a year and by the end of first year we were profitable and didn't need to invest anymore.

being a technical cofounder i did all the coding so the only expense was the server costs and also the design company to put together a nice layout for us. so overall, not much overheard.