Titan, a startup that is building a retail investment management platform aimed at the new generation of “everyday investors,” has closed on $58 million in a Series B round led by Andreessen Horowitz (a16z). The financing comes just over five months after Titan raised $12.5 million in a Series A round led by General Catalyst, and brings the startup’s total raised since its 2017 inception to $75 million. It values the company at $450 million. General Catalyst also put money in the Series B round, along with BoxGroup, Ashton Kutcher’s…