Well there are no perfect answers here … start-ups in the early days are basically all worth $0. You’ve accomplished nothing. You have no revenue. No customers.
But most professional U.S./Silicon Valley-style VCs and angels get worried if you sell much more than 30–33% of the company in the first round. 40% maybe if it’s a lot of money. Because there just won’t be enough left for the founders after the subsequent rounds of dilution.
Ideally, find a way to sell no more than 25% in the first round.
Don’t fail just because you didn’t raise that extra $25k.