10k would probably be good enough, realistically speaking. Or less. No idea 'bout the market price for a person and don't know how I would feel about giving away the ideal partner (plus one brat I don't want, I guess... Can't really think of a kid I'd like having, except if they generated income with their awesome supah-genius) for cash that won't make too much of a difference until it happened, but 100k is definitely enough.
Nothing particularly interesting. As far as I remember, I've always been extremely selfish and no one managed to convince me that's not the optimal path for maximum happiness through my life (alongside with planning for the future, having a more or less balanced diet and keeping as much money as possible, of course. Just being selfish won't do you much good) . Though if you want experiences, a teacher who was obsessed with logic and rationality (who had a pretty strict moral code, actually... Though I never saw the logic in it) and being exposed to extreme poverty (without living in it, thankfully) since ever may have gotten me like this.