How do we know when to go all-in on a player off the waiver wire after Week 1? Is D'Andre Swift an obvious value and trade target? With Trent Williams and Brandon Aiyuk officially back in San Francisco, is Brock Purdy no longer a sell? JJ answers those questions -- and more -- on this week's mailbag episode.       Sign up and deposit on Underdog now and use promo code LATEROUND for a free Late-Round Draft Guide and deposit offer: https://play.underdogfantasy.com/p-late-round-ff         Purchase the Late-Round Prospect Guide or the Late-Round Draft Guide: http://www.lateround.com/