I noticed that the price of 8 ounce (net) isopropane/propane fuel canisters has gone up considerably. I have a couple of full ones and a couple of half empty ones right now so I am ok, but here is my question:
Where is the most reasonable place to purchase these fuel canisters?

I'm aware of all the differences in fuel mix and brands, but for the coming summer I don't care at all what brand I purchase. What ever is cheapest will work for me this summer.
Jim

Walmart is probably consistently the most affordable place to buy them. You can also look into refilling. No cannister is designed to do it but many people successfully do it anyway. A good discussion on the topic can be found here:

https://adventuresinstoving.blogspot.com/2012/01/gas-canister-refilling.html

One thing to be aware of is that the cheapest place may not be available to you. Many retailers (including REI - search for "fuel canisters") cannot ship canisters to you; the only way to get them is to drive to the nearest retail outlet (to shop inside or use curbside delivery.) And, if you do find a place online that will ship, you'll need to add the shipping charge to the price to compare the cost at your local store.

I ordered 100g canisters from Amazon. 24 can be had as low as $5 per 100g canister, 12 about $5.50 per canister. Price includes shipping in the US. They are not as inexpensive as they once were.

I've been refilling my 100g canister for the last 3 years.

https://www.amazon.com/dp/B07DZKZPTC/ref=cm_sw_em_r_mt_dp_WGRETNM2YS58BFPR5A9V

just keep the can clean and dry should last 20 years