CREATE TABLE table_204_295 (id DECIMAL, "model" TEXT, "origin" TEXT, "type" TEXT, "version" TEXT, "in service" DECIMAL, "notes" TEXT)

how many maxi ambulance vehicles are in service ?
SELECT "in service" FROM table_204_295 WHERE "model" = 'maxi-ambulance'
SELECT "in service" FROM "table_204_295" WHERE "model" = 'maxi-ambulance'