Need some insight on this possible subject 2 deal

[Kenny Charles]

Hey BiggerPockets world!

I have a possible sub 2 deal looking to get some insight. I have a seller who owns a 3 family home, and willing to subject 2 her remaining mortgage balance of 295k. ARV is 485k, and as is value is mid 300k. She currently has a monthly mortgage of $2800 per month (taxes and insurance included) with a interest rate at 5.5. 2 units are rented out paying $1200, and the last unit pays $1050. Fair market rent is anywhere from $1500-$1800. Seller is willing to keep the mortgage in her name as long as we would like, but she is looking for us to give her a downpayment of 80k to pay off bills. We are going to try to renegotiate the downpayment. If we can't my partner and I are considering on giving her the downpayment, and then eventually refinancing the current mortgage to pull our money out, and lower the interest rate. Good or bad move?