Several options exist when it comes to the removal of a mole. Each comes with its own method--and its own price tag. Which is best is up to you--from the ultra-cheap (salicylic acid) to the more expensive (surgery). Other options with price-tags in the middle include a punch biopsy or the use of liquid nitrogen.
Punch Biopsy: $80-$100
You may want to consider a punch biopsy, which entails the use of a hole-punch-like device that cuts out a cylinder-shaped chunk of your skin--including the mole--leaving a small hole. The hole is subsequently sewn with stitches. The procedure leaves a small line-shaped scar.
Liquid Nitrogen: $50-$100
If simple and cheap is what you're looking for, liquid nitrogen may be your best bet. Using a liquid nitrogen "gun," a physician sprays the mole with liquid nitrogen for a prolonged period--typically from 20 to 90 seconds, depending on the size of the mole. This can be painful because the liquid nitrogen penetrates into the skin surrounding the mole. The purpose is simply to kill the cells in the mole. After about a week, the mole will simply fall off, usually after being bumped or scraped by something.
Salicylic Acid: $6-$35
For an even cheaper solution, consider using salicylic acid, a peeling agent. Its application to the skin causes the outer layer to shed wherever the acid comes into contact with it. It is used to "burn" off moles as well as warts, corns, acne and even dandruff. This should be done by a qualified physician, of course.
It's a little more costly, but surgery will almost always do the trick. Mole removal surgery involves the anesthetizing of the mole area before one of three methods is used. There's the simple shaving off of the mole with a blade. This is often used when the mole is especially protruding. A second surgery is cauterization, which involves the literal burning off of the mole. A third surgery type, the excision method, entails removing the mole and some surrounding skin with a blade, then stitching up the skin. This last form of surgery is generally employed when the mole is suspected of being cancerous.