What can I do if my employer wants to patent my idea?

If you have someone that wants to purchase your provisional patent it will be up to you to name your price. If you decide to go through with selling your patent, you must make sure that there is a contract providing for you to get royalties from this product. Meaning, every time the Buyer makes money, you make money also. I highly suggest that you have an attorney review any contracts you sign. If you are not able to pay for a patent attorney, then there are legal aid services in your local area that will get you in touch with one for either free or a reduced rate if you qualify.

Sounds like all you need is for an attorney to draft an assignment or a license for you. Has this company committed to buying your rights? If so then they should have their attorney draft the agreement at no cost to you. However if you are looking for a patent attorney to write you a full utility patent for free - good luck! I would suggest looking for investors.