Cartago is the former capital of Costa Rica and is a fully functioning city by itself. It also acts as a suburb of San Jose and is a stop along the way to the Caribbean coast.
Cartago commercial rentals encompass everything you will find in the Central Valley but in a smaller area. The area around the famous church has many restaurants and stores and will be preserved as as a historical site, so keep in mind that large scale development within these 100 or so blocks is unlikely.
Neighborhoods in Cartago are named and used frequently in giving directions. The downtown area is known as Occidental. You enter the city on the West side from San Jose by passing through San Nicolas.
You will also find there is a technology community in Cartago. The Costa Rica Institute of Technology is located in the Oriental neighborhood, a few blocks from the Basilica of Los Angeles.
You will find hardware and other supply type stores along the major routes to San Jose and to the coast. There is also a central market where smaller stalls are available for rent and cater to a strictly pedestrian type of customer.
The population of Cartago is highly diversified in terms of class and origin, so businesses renting in Cartago will find many market segments to address.