Erect them in open areas between 10 and 20 feet high and at least 40 feet from trees or buildings that are taller than the martin houses. On one hand, the farther the housing is placed from trees, the better. On the other hand, martins like being near humans. Cluster multiple houses within 10 feet of each other. They readily use perches on and near the houses.
Some landlords erect TV antennas near or among the martin houses for the birds to use as perches.
Sometime ago she rescued an in injured red screech owl from the highway and nursed it back to health. It stayed around for a long time and she kept it in a cage outdoors and let it out when it was ready to be released. It came back for a time to eat. She has quite a lot of wildlife in her area and is a true nature lover. You certainly have birds and wildlife to enjoy.