[ercoupe-tech] Parts Receipts

[hatfielddennis]

I asked a seller on E-bay if he would provide an original sales receipt 
for a tire and tube I considered buying for my 415C.  He told me that 
he did not have it and in his 40 years as an A&P he had never put a 
parts receipt in a log book. Can someone please tell me if parts 
receipts belong in an Ercoupe maintenance log book?