Can mom get $250K primary home exclusion?

[Don Darnell]

A number of years ago I bought a primary house for my mom due to her bad credit. She paid all closing and down payment costs. I paid the mortgage initially for four years and she covered all remaining household costs. After the four years, I continued to make the payment and she reimbursed me. My mom has paid for multiple renovations and paid $60K to pay off the mortgage. On paper I own the house, but she has always been the owner. She would like to move to a retirement home now having lived in the property for 10 years. What would she/I need to do so she can claim the $250K home exclusion since not my primary home? 

Thanks,

Don