Always put contingencies aside. During any renovation, it is critical to set aside money for the "what if" or emergency scenarios. For example, there might be plumbing that you didn’t anticipate needing to replace. Conventional wisdom suggests adding 15 to 20 percent to your contractor’s renovation cost to safely consider these contingencies.  Photo 4 of 10 in Space-Saving Modern Built-Ins by Erika Heet from Ray Kappe’s Multilevel House in Los Angeles

Space-Saving Modern Built-Ins

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Always put contingencies aside. During any renovation, it is critical to set aside money for the "what if" or emergency scenarios. For example, there might be plumbing that you didn’t anticipate needing to replace. Conventional wisdom suggests adding 15 to 20 percent to your contractor’s renovation cost to safely consider these contingencies.