My wife is a nonemployee, and she only made 6700 last year. We did buy a truck because her vehicle was breaking down, can I write this as an expense?

It depends. Only the allowed business miles divided by total miles for the year will be allowed as an expense.

It appears as though this truck is less than 6,000 pounds. Driving to and from the camp may be commuting miles which would not be allowed, however if she must drive other places and if as you indicated, she must move set pieces around then those miles would be allowed. Driving to purchase or pick up certain supplies would also be allowed.

Commuting expenses. IRS Publication 463 (more information to help you)

You can’t deduct the costs of taking a bus, trolley, subway, or taxi, or of driving a car between your home and your main or regular place of work. These costs are personal commuting expenses. You can’t deduct commuting expenses no matter how far your home is from your regular place of work. You can’t deduct commuting expenses even if you work during the commuting trip.

In this case you can use the standard mileage rate (SMR), of $.67 per mile. If you don't use it the first year a business vehicle is placed in service you can never use it on that vehicle.

• The IRS mileage rate for 2024 is 67 cents per mile for business use. 
• In 2025, the rate will increase to 70 cents per mile for business use.

To use actual expenses the total business miles divided by the total miles for the tax year will determine the amount of the expenses allowed.

Once you determine the business use percentage this will be used for all actual expenses you may have paid for the F150. Add 'Vehicle' expense in the business section and then TurboTax will ask all the questions for you to decide which you would choose to use for 2024 (SMR or actual expenses).