In the country of Óxisz the minister of finance observed at the end of the tax census that the sum of properties of any two neighboring city counted in dinar is divisible by $1000$, and she also observed that the sum of properties of all cities is also divisible by $1000$. What is the least sum of properties of all cities if the map of the cities looks as follows? Remark: The cities may have non-integer properties, but it is also positive. On the map the points are the cities, and two cities are neighboring if there is a direct connection between them.