Since employment-based Adjustment of Status requires sponsorship, you would need to have a sponsor regardless of how much money you may have saved. This is the case unless you self-sponsor via the national interest waiver or extraordinary ability.
None of the employment-based petitions are determined by the amount of money you have in the bank. There are some employment-based petitions, such as the EB5, or the investor visa, which require you to invest a particular amount of money depending on the geographic location of that investment, but you would not have to have the money in the bank. That money would need to be invested in a business opportunity to apply for Adjustment of Status.