It typically costs between $10,000 and $50,000 to build a backyard guest house. The cost varies depending on the size and features of the guest house.

In most cases, it costs anywhere from $15,000 to $50,000 to build a backyard guest house. However, the final price will largely depend on the size and features of the guest house. Some important factors that will affect the cost include the roofing material, the type of foundation, and the type of siding. If you want your guest house to have electricity, plumbing, and heating/cooling systems, those features will also add to the cost.