I am not am anti-vaccine person by any definition, as I have had plenty of vaccinations in my life.
However, I recently had to do a risk assessment for myself for Japanese Encephalitis, which is a $400-800 vaccine that only has a few years of effective dosage at best, and has a mortality rate of 16,000 per year out of 4 billion exposed.
If there's any chance that the vaccine has some type of chemical or substance that would cause an adverse effect in me, even if it was free, I would take my chances without the vaccine.
Similarly, I haven't received a tetanus shot in decades, despite really wanting to. I simply don't have the money because I don't have insurance, but I feel the risks of the vaccine are worth the benefit of not having tetanus.