Costs incurred by the homeowner would be limited to appraisal fees, home inspections, and costs (legal or otherwise) incurred in the sale of your home to the non profit.  It may help if you looked at this process in this way...  Youve signed up with USAHomeRaffle.com in order to say, Non-profit please buy my home so that you can use it for a raffle.

The non profit organization assumes all responsibility of carrying out a successful raffle.  Once the raffle is underway, your job is really just to help with ticket sales and potentially be there for any media coverage or open houses.  All costs relating to the actual raffle (marketing, administrative, legal, reimbursements, etc.) are handled by the non profit organization.