Solutions :

3-letter words (1 point): 41

BEE; BES; CEE; CIS; COR; ECO; EIK; ERE; ERS; EVE; ICE; ICK; KIS; KOI; KOR; OES; OIK; ORC; ORE; ORS; REB; REC; REE; REO; RES; REV; REX; ROC; ROE; ROK; SEC; SEE; SEI; SER; SEX; SIC; SIK; SKI; VEX; VIE; VIS.

4-letter words (1 point): 51

BECK; BEER; BEES; BERE; BREE; BRER; CEES; CERE; CERO; CIVE; CORE; CORS; CREE; EIKS; ERES; EREV; ESES; EVER; EVES; ICER; ICES; KORE; KORS; OIKS; ORCS; ORES; REBS; RECK; RECS; REES; REVS; ROCK; ROCS; ROES; ROKS; SECO; SECS; SEER; SEES; SEIK; SERE; SERS; SESE; SICE; SICK; SKIO; VERB; VERS; VICE; VIES; VISE.

5-letter words (2 points): 45

BECKS; BEERS; BERES; BESEE; BESES; BREER; BREES; BRERE; BRERS; BREVE; CERES; CIVES; CORER; CORES; CORSE; CREES; EREVS; ERSES; ICERS; KIEVE; KIORE; KORES; REBEC; RECKS; RESEE; RESES; REVIE; ROCKS; SCORE; SCREE; SEERS; SERER; SERES; SERVE; SEVER; SICES; SICKO; SIEVE; SIVER; SKIVE; VERBS; VERSE; VICES; VISES; XEBEC.

6-letter words (3 points): 27

BESEES; BEVIES; BREERS; BRERES; BREVES; BREVIS; CORERS; CORSES; CREESE; KIEVES; REBECK; REBECS; RESEES; REVIES; REVISE; SCORER; SCORES; SCORSE; SCREES; SERVES; SEVERE; SEVERS; SIVERS; SKIVER; VERSER; VERSES; XEBECS.

7-letter words (7 points): 11

REBECKS; RESCORE; RESERVE; REVISER; REVISES; SCORERS; SCORSER; SERVICE; SEVERER; SKIVERS; VERSERS.

8-letter words (11 points): 7

BREVISES; REREVISE; RESCORES; RESERVES; REVISERS; SERVICER; SERVICES.

9-letter word (11 points): 1

SERVICERS.