When I was building custom homes, we wrote off every expense including the truck and camper against the business, even when we were on 'information gathering' travel trips into the Rockies, Sierras and Mojave areas.
We were studying those areas and architectural history for design ideas for the homes we built, and touring the timber industry for information about lumber, and other industries for structural components. Shot a lot of photographs for use in our designs.
We survived two IRS audits ... and not one deduction was disallowed. It often depends upon how the books label various expenses, and if you can use that information for your income production.
