My score is low 500. Get mortgage for home loan

I am trying to purchase my first home. My credit score is in the low 500. My mortage company told me to try to pay off some of the things on my credit record so that my score will go up. 1. I have 30 days to close. will that be enough time. 2. My realtor told me I could do a straight mortage or bond for deed. She had me to sign a contract and now I hear nothing about the bond for deed I am using all my money trying to pay off old debts. Will this help me to meet the deadline.
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you will have to ask your realtor that question
get recipt of payments
use recipts for proof of payment
you can dispute items as you pay them to speed the credit report update process
say paid off in full, or paid as agreed
I did a straight mortgage to get financed on my first home 6 mos later i got a fixed rate mortgage. Is this what the realtor is talking of?