I have come across a large stamp collection that I have been asked to sell. I mainly deal in sports cards and memorabilia so I'm not particularly knowledgeable in this area although I have sold some stamps before.
I'll attempt to make this post as organized as possible but forgive me if I get off track, I have tons of questions.
The collection consists of approx 10,000 stamps from all different countries ranging in year from 1870-1975 (these are the newest and oldest ones i've found and i've only looked through 2% of the collection). They are stored in these wax paper like envelopes, most of which have some writing on them indicating what they are. Unfortunately, there is so much writing on the envelopes, I cannot tell what any of it actually means. For example ...

My ultimate question would be what is the value of a collection like this? I can provide as many scans as needed to help show what I have but since I have no idea where to start, I figured I would ask you guys before wasting my time scanning useless stuff.
A list of countries I know I have for sure are:
Great Britain
Malaya
Singapore
Southern Rhodesia
Tanganyika
Trinidad & Tobago
Papua New Guinea
St. Lucia
British Guiana
Ceulon
Pakistan
Sarawar
Rhodesia
Canada
Poland
Hong Kong
Egypt
Jamaica
Argentina
India
Belgium
New Zealand
Norway
Italy
Finland
French Maracco
Brazil
Netherlands
Japan
Australia
France
USA
There are also probably dozens of other countries but the ones I listed above were already separated.
The majority of the stamps seem to be used and I have up to 50 of any given stamp. So help me out people! Where do I start in order to figure out what I have??
Thanks in advance for any help!
-James