Have to chime in on this one.
As a melanoma surviver, I definitely recommend seeing a dermatologist and having any suspicious moles removed. As someone above said, a couple hundred dollars is worth your life. Plus... if you have no insurance and are lower income, you should talk to a social worker as there may be some program or low-cost insurance available to help you.
Ironically, I have only had five moles removed. Two were "normal," two were displastic, which is abnormal but not cancerous, and one was a melanoma. The rest of my moles, my derm says are all "in the same family" as the others, though we've got our eye on one suspicious one that I think is going to come off soon!
The melanoma was exactly in the center of my chest and was one my derm said w had to watch. One day I noticed that it had gotten darker and looked like it was slightly flakey in the center. I immediately made an appointment and sure enough, it was a Melanoma. Luckily for me it was just on the surface and had not spread down into the deeper layers of skin. The University of Michigan Cancer dept did a Wide Area Exscision and removed a chunk of skin 2" long by 1.25" wide from the center of my chest.
It took a while to heal, but with some daily moisturizing cream, the scar is barely noticable today. :-)
My most recent mole came back displastic with pigment the whole way to the perimeter (edge) so my derm had to go back and re-remove it, taking more skin. That was annoying, and is taking a long time to fade... so definitely ask the doctor to take a good perimeter of "normal" skin around the mole - just to be sure.
And always wear your sunscreen.