The money contributed to an annuity may be in post-tax dollars. When you contribute after-tax savings to an annuity, you can generally put in as much money as you like.
Expenses can vary.
Make sure that the annuity contracts you consider have competitive fees. Independent rating services such as Morningstar and Lipper Analytical Services both publish reports that compare variable annuity fees. Your local library may have copies. While cheaper doesn't necessarily mean better, if a contract is too expensive it could offset gains from the tax-deferred status. All earnings from annuities are taxed as ordinary income.