Can you add contractor bills to HUD

[Ryan Cleary]

Forgive the lack of correct terminology as this is my first time hearing about this.

I am in contract to purchase a multi family property for 155k with a 2% seller credit. I know this property has the opportunity to appraise for higher than contract price. The property needs new windows. I have heard of people contacting the title company and adding a contractor bill which will then be wrapped into the mortgage. Is this fiction?