Purchase/Transfer a House

I want to purchase a house from my mother. I am going to purchase the house for what she still owes on it ($275k). We want to avoid any real estate agents being involved.

I am completely new to all of this and would just like some general info on the steps that need to take place in order to make this happen.

All I have done is gotten pre-approved for the loan amount to cover what is still owed on the house (the $275k).

What kind of legal services do I need?
Can a lawyer completely take care of this entire process (or do we need to involve other people)?
How much should i expect to pay for completing this process?

Any other info is appreciated.