Open Question: Purchase parents house with FHA loan or can we transfer their loan?

I wish to purchase my Mother and Father's home. I am a first time home buyer and due to Credit score around 600 FHA loans are appealing to me. The home value is est. $195k, we have agreed upon $160k for a purchase price. My parents carry est. $145k mortgage within that a est. $100k is in home equity loans at 2.5%. Is there a way to transfer the title completely and assume their mortgage which carries a lower interest rate? or do I shop mortgage brokers? or credit unions and banks better?