Colorado homebuyers have struggled for years with slim pickings and unfavorable conditions. But a monsoon of listings in recent weeks may finally end the supply drought. Statewide, the inventory of homes and condos available for sale at the end of June shot up from 19,790 a year ago to 24,365 last month, a 23% increase, according to counts from the Colorado Association of Realtors. That aligns with the 23.6% annual inventory jump that the National Association of Realtors measured for June nationally. Those averages mask wide variations within the country and the state.