Indie Record Deal Advances Explained
by Tamera H. Bennettposted November 18, 2008
Here is a link courtesy of Know The Music Biz to a good general explanation of how an indie record deal works in regards to advances of recording costs.
I would just add that even though mechanical royalties are not usually calculated into the advance, they are an ongoing expense of the record label and will be deducted from gross profits before artist royalties are paid in a 50/50 deal.