3 letters:
b's, b.s, bes

4 letters:
b.'s, beam, beas, beem, bees, bima, bums

5 letters:
balms, beads, beahm, beals, beans, bee's, beese, beres, biers, bombs, booms, deems, eames, hiems, nemes, reams, seams, seems, siems, teams, teems, weems, beams

6 letters:
beales, beamed, beamer, bean's, beemer, beer's, biev's, bomb's, boom's, reames, team's, teams', themes