The Penthouse Pact by Cathryn Fox is the story of  Parker Braxton and Layla Fallon.
Layla is a young college student working a full time job and trying to get by.  Parker is a young rich business man who is hard nosed about everything.  But when he anciently hits his car into Coffee Barista named Layla he start showing another side.  Parker and his college buddies had made a pack never to marry and if the do they had to give each a large sum of money.  Parker was so sure of himself but Layla is making him start to feel totally different.  Layla isn't a yes person and isn't really impressed with his money....she just wants to work hard and get through college.  
I really enjoyed seeing these two come together.