Utilize your financial knowledge, give your answer or opinion to the input question or subject . Answer format is not limited.

What are the ins/outs of writing equipment purchases off as business expenses in a home based business?
First of all, Dilip's answer explains well how the business deductions generally work. For most (big) expenses you depreciate it. However, in some cases you need to capitalize it, which is another accounting method. When you capitalize your expense, it becomes part of the basis of the product you're creating. Since you're an engineer, this might be relevant for you. Talk to your tax adviser. How exactly you deduct/depreciate/capitalize things, and what expense goes which way depends greatly on the laws and jurisdictions. Even in the US, different states have different laws, and the IRS and State laws don't have to conform (unfortunately). For example, the limitations on Sec. 179 deduction in 2010-2011 were 20 times higher on Federal level than in the State of California. This could have lead to cases where you fully deducted your expense on your Federal tax return, but need to continue and depreciate it on your State return (or vice versa). Good tax adviser is crucial to avoid or manage these cases.