1step,rule,n_before,n_after,n_removed,rationale21,line parses into exactly 5 CSV fields with sale_id matching S+5 digits,1200,1164,36,garbled/corrupted export lines cannot be read unambiguously; not reconstructed32,"municipality in control list, valid ISO date, numeric price (plain or quoted thousands-separated), positive numeric area",1164,1164,0,fields must be readable unambiguously43,unique sale_id (drop exact duplicate ids),1164,1164,0,sale_id is documented as unique5