Sometimes, usually her "outdoor" shoots, anything outside her apartment I'm almost positive she's paying a "cosplay cameraman" like the ones that go to conventions.
There are two kinds of cosplay shutterbugs, the ones who do it for free and the ones that get paid. There's also people who give their friends a free pass, but that's obviously different.
Depending on where you are, it's easy enough to find someone with a DSLR who'll do it for free. Or for exposure, or to practice with their camera, or other benefits, whatever an unemployed BPD might be able to offer. Maybe they're a student who needs a model for a project, maybe they go all gooey around a girl in a tight costume, whatever. They might advertise, but more likely just wander around cons and maybe ask the cute D.VA if she wants to do a shoot at a later date (she doesn't). There are also cosplayers who pass out cards to guys with DSLRs at cons. I've got dozens of them.
Upside: Free, beyond credit and a shoutout on social media. Students probably have some photoshop skills and want to make it look good.
Downside: You get what you pay for.
Then we come to paid photogs. There are two kinds of these: "I'm a real photographer!" and real photographers. "Real" photographers do paid shoots at cons, but your milage may vary with that. I've seen people advertise shoots at $30 CND for 15 minutes. The quality of what you get will vary. Depending on where the con is, or what kind of crowd is there, the best spots might already be taken, there could be time limits at good spots, you can't really keep people from wandering around in the background and people lose track of time very easily.
Upside: They probably know how to work a camera.
Downside: Cons are chaotic, your costume might look worse for wear after a few hours at the con, weather might be shitty, they might never get back to you, they might not know how to use photoshop and just send the plain jpgs. Shit happens, basically.
Real photographers, and by that I mean pay taxes, have the gear and experience, have a studio, can be expensive. I've seen guys charge $150 American for three photos. A lot of them charge cosplayers more because they're seen as having more money but less experience with stuff like this.
Upside: They know how to photoshop, they have lighting gear, know where to shoot if you're doing an outdoors shoot and to talk to about it, and the shoot is much more controlled. No drunk Pikachu's blundering around in the background, no dumbasses photobombing you, stuff like that.
Downside: Cost, and you might have to wait a while, depending on the season. During wedding/Communion/Confirmation season, cosplayers are probably going to be low on the priority list.
Paid photogs in general almost always prefer cash payments, because taxes are the devil. When I worked in a studio, every camera guy told me they were cash only outside office hours. She most likely is trying to get someone to do it for free as exposure or other benefits, which might work. I'll admit, I've fallen for it myself a few years ago. I know she's hired photographers before, but I can't see her coughing up a lot of physical cash now.
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