For detailed costs, bonuses, and requirements of all buildings and resource fields, you can use the statistics tool below.
At the top of the tool, you can set parameters like game speed, Main Building level, fealty level, and prestige level (visible in the lobby under "Account"). The values update instantly.
Within each table, you can select rows to calculate totals, for example the time and resources needed to upgrade a building from level 10 to 15.