"my book values of my inventory items at my retail prices "
Inventory must generally be valued at cost.
To calculate your cost of goods (for example):
Opening Inventory (12/31/2006) 100,000
Purchases during 2007 50,000
Available for sale 150,000
Closing Inventory (12/31/2007) 80,000
Cost of Goods Sold 70,000
If your sales for the period were $120,000, your gross profit would be $50,000 ($120,000 less $70,000)
From your gross profit, you deduct your expenses such as:
Advertising
Office
Communications
Travel (car)
Listing Fees and Commission
Occupancy
Bank Charges and Interest
To arrive at your Net profit (line 135)
As far as car expenses are concerned (I own my car), I find it much easier NOT to depreciate but to use a flat charge of $0.50 per km for business use during the year. If you use your car for business purposes for 5,000km, a $2,500 would be deductible. One must keep logs.
I was audited for the last two years and that simple method was accepted without question.
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