I made a simple one for my Latte and it only took a few hours, probably given my terrible skill at using tools. I got a 2.5 x 2.5 of ply wood covered with carpet as a base, nailed in a 3 ft piece of wood wrapped in sisal rope for a scratching post. I also nailed in a 3.5 foot piece of wood with a 2 ft. piece of the cardboard tubing (used for pouring concrete forms) cut in half as and covered in carpet as a napping spot. Latte likes it, and it is simple. All told it cost me less than $20. You could easily add on to this for a more complex design.