The Affidavit of Support (I-864) requires lengthy documentation of your financial situation. Most submit tax returns, bank accounts and assets valuations. The Application for Adjustment of Status (I-485) requires support documentation and biographical information.
The general rule is that a legal permanent resident must be a resident of the U.S.A. for 5 years after obtaining legal permanent residence status OR be married to a U.S. citizen for at least 3 years.