Hi
One important advise to all whose files has been tranferred to Detroit
I have read in their website that they will use either standard delivery or Canada's Xpress post to return the immigration documents or passports to Canada. They don't accept any commecial couriers to return the documents. Please read the below::
http://www.canadainternational.gc.ca/detroit/imm/return-retour.aspx?lang=eng
HOW TO SEND YOUR DOCUMENTS TO THE CONSULATE:
FOR RESIDENTS OF THE USA
1.If you live in the USA, you may send your application, documents and passports by mail or any commercial courier to:
Canadian Consulate General
Immigration Section
600 Renaissance Center, Suite 1100
Detroit, MI 48243
FOR RESIDENTS OF CANADA
1.If you live in Canada, you may send applications, documents and passports by mail, (not by commercial courier) to our mailbox in Windsor, ON Canada. The Post Office in Windsor will not accept commercial courier deliveries.
Canadian Consulate General/IMM
401 Ouellette Ave
P.O. Box 940 Station “A”
Windsor, ON N9A 6P2
CANADA
2.If you live in Canada you may send immigration applications, documents and passports by mail or commercial courier to our address in Detroit. Courier packages must only be sent to the Detroit, MI address.
Canadian Consulate General/IMM
600 Renaissance Center Suite 1100
Detroit, MI 48243-1798 USA
HOW THE CONSULATE WILL RETURN DOCUMENTS TO YOU:
DOCUMENTS WILL NOT BE RETURNED TO YOU BY ANY COMMERCIAL COURIER UNDER ANY CIRCUMSTANCE.
FOR RESIDENTS OF THE USA
STANDARD PROCEDURE: The Consulate will return documents to addresses in the United States via U.S. Postal Service First Class Mail (Regular Mail). No tracking system available. Provide a self-addressed envelope.
U.S. EXPRESS MAIL: If you prefer U.S. Postal Service Express Mail, please enclose with your application a PRE-PAID flat rate U.S. Express Mail envelope. The correct U.S. postage must be affixed. Enter a daytime telephone number and your complete address in the "TO" section of the mailing label. Enter the address of the Consulate in the "FROM" section of the mailing label ( Canadian Consulate General, Immigration Section, 600 Renaissance Center, Suite 1100, Detroit, MI 48243-1798 USA). Make a note of the tracking number for each envelope.
FOR RESIDENTS OF CANADA
STANDARD PROCEDURE: The Consulate will return documents to addresses in Canada via U.S. Postal Service First Class Mail (Regular Mail). No tracking system available. Provide a self-addressed envelope. Please note that regular mail to Western and Eastern Canada can take up to three weeks for delivery.
CANADA POST XPRESSPOST: If you prefer Canada Post Xpresspost , please enclose with your application a PRE-PAID Xpresspost envelope. Complete the mailing label on the return envelope showing the Windsor Post Office Box address in the "FROM" section of the mailing label (Canadian Consulate General/IMM, 401 Ouellette Avenue, P.O. Box 940 Station “A”, Windsor, ON N9A 6P2 CANADA. Make a note of the tracking number for each envelope. Please note: If you choose to select this service, your package will be sent from our P.O.Box in Windsor and will not originate in the USA..
Please Note:
Applicants who send their documents to us by mail must provide a return address in Canada or the United States to which their passport(s) can be returned.
These instructions are subject to chage without notice.
THE CONSULATE IS NOT RESPONSIBLE FOR ANY PASSPORTS
I am not sure what do you mean by paid 250 for in person stamp..... I live in Canada now, do you live in US? 
