Prefabricated islands are much less expensive because they are mass-produced. The average cost for a permanent prefab kitchen island is $2,500 to $3,500. But those on a tight budget can get a prefab rolling island for as little as $100.

The average cost to install a kitchen island is $800 to $2,500 for a prefab model or $3,000 to $6,000 to build a custom island, depending on the size, style, material, and features.

When planning a kitchen renovation, adding an island to your new kitchen is a great way to increase both counter and storage space. Considering that people always seem to need more of these two things, it's a huge win.

While there is no one-size-fits-all answer, a general guideline is to aim for a width of at least 24 inches and a length that makes sense for the size of your kitchen. For smaller kitchens, a compact island of around 3 by 4 feet can provide valuable workspace without overwhelming the room.