A lender would likely approve you up to $159,148
On $56,000 of gross income with $550 of existing monthly debt, the 28/36 rule supports about $1,130 a month toward housing. With $20,000 down at 6.65%, that reaches roughly $159,148 — a $139,148 loan at 12.6% down. Your resulting debt-to-income ratio would be 36%, and you are currently limited by the total debt.