Following are required for AP:
------ I made few corrections
1. Application form (I-131) for Application for travel document. and write any reason on cover letter for AP
2. Application fees (Check current fees at uscis site)$ 165 payable to USCIS
3. 2 Photos with I-485 receipt number and name, DOB, A# written on back of photographs with pencil
4. Affidavit/Supporting letter for Advance parole.( that is NOT needed)
5. Copy of I-485 Receipt Notice.
6 Color copy of your driving Licence and Color copy of first page of your passport that has your name, Photo, PP# and DOB
7 copy of I-94 both the sides front and back( it does not matter if I-94 is expired)
8 if you have I-140 filing reciept OR I-140 approval notice attach the copy( if you dont have no need)
** if spouse is filing then send copy of marriage certificate
** write on the cover letter documents attached and any reason for AP like visiting old parents or vacations( they dont care)and at top of letter write your Name, DOB, A# and pending I-485 recept # that starts with EACor WAC or LIN..... Sign the letter with name and address
send the all documents by certified mail and out side the envelope write in big bold letters Form I-131 for Advance Parole
You don't need attorney if you have all of the above