owner finance

our landlord wants to sell us her home which she owns free and clear. she is willing to owner finance. can we take out a mtg or home equity loan for the down payment using the house? house value is $272,000, she is selling to us for $200,000 because it is very outdated and in need of lots of cosmetic repairs. we were going to see about getting a loan for $100,000 giving her $50,000 for a down and $150,000 owner finance.