Hello,
As this is a very easy and straight forward job as you have said, I can do this job for the lowest amount that you can pay. I'm still new at Freelancer, so I don't mind getting a small payment at the moment since this job can help me build my portfolio. Although I'm not an expert when it comes to advertising on Craiglist, I pretty much have experience with running ads on Facebook. I had an e-commerce shop 2 years ago and had to do all the stuff from the ground up.
If you like my proposal, I would like to hear from you.
Best Regards,