I'm a big fan of low serial numbers. I must of had at least 30 notes with serial number 00000012 when I sold my collection. Years ago you could get a modern, uncirculated $1 FRN with a 2-digit serial numbers for under $100. I paid close to $500 for a 1935 $1 Silver Certificate (H00000012A) in a 64PPQ holder. The price paid sounds reasonable.