use probability sampling method

If you plan to divide houses into groups based on characteristics, such as urban and rural areas or different regions. Randomly select houses from each group. Collect data on sale prices and ages within each group. What probability sampling method is used in this case? If you plan to divide Mississippi into clusters, like counties or cities. Randomly select clusters. Then collect data on sale prices and ages from all houses within the chosen clusters. What probability sampling method is used in this case