SoFi Technologies (SOFI 2.56%) hasn't been an easy stock to own, with the price bouncing up and down. Case in point: Its 52-week high is 206% above its 52-week low. However, shares have soared 154% in the past 12 months (as of June 26). The market is warming up to this digital banking leader.This fintech stock is extremely volatile, which might continue to be the case. But shares still trade well below $20. Should investors add SoFi to their portfolios at these levels? SoFi continues to innovateSoFi has fou ...