Humidity. The most common cause of condensation on double-glazed windows is humidity. The outside window is colder than the inside window causing fog or frost to build up in-between the two panes. The window and house is extremely airtight and cannot breath.
Small-to-mid-sized businesses can expect the cost of software and services combined to range anywhere from $150,000 to $750,000. Certainly a significant investment, but a properly implemented ERP system will pay for itself quickly.
Now the main question is, how much it costs to develop a Drupal website from scratch. If you are lucky then there will be no additions required and the already available open-source and modules will be sufficient for the development of the cost. A basic Drupal project may cost from $30,000 to $40,000.