Value Of British Empire Queen Victoria Revenues

A friend of mine's father died and left an extensive worldwide collection that I am helping to evaluate. The postal part of the collection has a catalog value of between $40-50,000 based on a 2006 Scott catalog. The revenue stamps I have no idea about, so I post a few pictures and ask the question, do they materially affect the total value or are they just very nice looking revenue stamps.

Great Britain


Canada



British Empire





I can do an individual scan of any stamp if need be

All revenue stamps have value just like the postage types.Collectors search for these.

check this link for revenue stamps by country for an idea;

https://www.revrevd.com/mauritius.html
just an example;
https://www.ebay.ie/itm/CANADA-BILL...AOSwmFhbyef9

Is there anything from Malta?

Thanks perf12. I knew they had value, just needed to know if it was high enough that I needed to include it in the overall valuation of the collection and I guess I do.

Unfortunately nothing from Malta. Countries represented include Great Britain, Canada, New Zealand, India, Hong Kong, Egypt, Ireland, Mauritius, Cape of Good Hope, Queensland, New South Wales, Straits Settlement and Isle of Man

Canadian revenue values from 2009 Van Dam catalog

9c orange bill stamp 1865 2nd issue #FB26 $5.00 used
$1.00 red & green center 1865 2nd issue #FB33 $225.00 used
$1.00 green & red center 1865 2nd issue #FB34 $200.00 used
$1.00 blue & black center 1868 3rd issue #FB52 $12.50 used