One of the major differences between Heroes V and Heroes III is the diversity in the town build plan. While Heroes III contained a relatively linear distribution of structures and prerequisites, Heroes V introduces another variable: Town Level. Each town is assigned a town level depending on the number of buildings built. Since city plans are more complex in Heroes V, they've been broken down into 3 separate sections for each town.

Standard Buildings
Standard Buildings are common to every town, and include structures such as the defensive upgrades (Citadel, Castle), economic upgrades (City Hall, Capitol), and other miscellaneous structures like the Tavern, Marketplace, and Blacksmith. These buildings cost the same in every town, and have standardised requirements.
- Haven | Inferno | Necropolis | Dungeon | Academy | Sylvan -

Magic Buildings
Magic Buildings include structures that are unique to that specific town. Generally, these encompass creature boosting structures (e.g. Halls of Horror), buildings that aid or are required for the town's racial ability, the mage guilds (which have a common price), and another special building.
- Haven | Inferno | Necropolis | Dungeon | Academy | Sylvan -

The Dwellings of each town follow 3 main price structures in terms of Gold costs. Haven, Academy - maximum gold for level 7 is 30,000. Dungeon, Inferno - maximum gold for level 7 is 25,000. Necropolis, Sylvan - maximum gold for level 7 is 20,000. Each have varying resource costs, and each town primarily relies on one resource, two in the case of Sylvan and Inferno.
- Haven | Inferno | Necropolis | Dungeon | Academy | Sylvan -

Thanks to ThE_HyDrA for creating and looking after the Heroes 5 section of Age of Heroes!