Removing Numerous Settled Accounts

Hello, My wife and I are trying to repair our credit in hopes of owning our own home within the next 6-12 months. We previously owned a home but were days away from foreclosing and we did a short sale. It was a USDA Rural Development Loan. We also had numerous credit cards and other unsecured debt that we hadn't paid on for a long time. All of the accounts had gone to collections except maybe a few chase cards. We ended up paying out a settlementabout 2 1/2 to 3 years ago on each account to bring all of the accounts to a zero balance and closing out the accounts. We currently only have a Student Loan that we are paying on and have not missed a payment now for almost 1 1/2 years. I have read quite a bit about people requesting the credit companies or collection agencies to remove the negative entry or change the status from settled to paid... Do I have the right thinking process or should there be other steps that I need to take... We are desperately needing to get our credit fixed and our scores up!!! Any and all help is greatly appreciated...

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Annuity