How do I investigate a (possible) monopolistic market?

I'm doing this at a high school level for my economics research paper and I'm not sure if it's beyond me. However, there is this supplier of school uniforms for numerous private and public schools around my area and it is the only supplier. (There's another mini-supplier although they only sell boys trousers which is grey and same for every school)



I'm not sure if I'm able to collect the information as I'm pretty sure they would be very reluctant to give it to me. Is there any way I can obtain it?



And also, I'm not sure how and in what aspect I would investigate it in.

I've looked around for sample research papers on monopoly as a reference in the ways they analyse and collect their data but I haven't found any. So any suggestions would be appreciated. Thanks.How do I investigate a (possible) monopolistic market?
The issue would not be that there's a lack of competition. The issue is if there CAN'T be any competition. If they're selling black blazers for $49.95, they can get away with that. If someone else steps in that can sell them for $24.95, they can't drop their prices to, say, $3 each to drive the other company out of business.

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