Bring used parts into canada?

You pay a tax on the value on the bill of sale of the used part.The key is,making a bill for a small amount,if the distributor cost 40$ you make a bill for 10$,as its your word against theres.You also have a alotted amount for the time you spend in the states.You admit you bought items if you where their for a day or 12hours,and have spent 75$ or less in the items bought,if they say any thing,you have the low ball bills to prove it.And if you have a freind in the states,he/she can have there address on the bill to prove they bought it from them.When you get good,you can buy a car in the states and bring it across the same day and only pay 37$ in tax for a 67 dart,mrmopartech