Hi Kamesha, great question. The cost of good sold account is generally used to keep track of items that are a direct cost of the products that you sell. If you track the parts in a cost of goods sold account, it will allow you to see what your gross profit is before other expenses are deducted.
However, since your husband is being reimbursed for all of the parts that he purchases, I think tracking the parts as an expense is better. So unless he stops getting reimbursed from his customers, I would continue to post the parts to the expense account like you have been doing.
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