Help selecting between wire/folding tires
For most of us it makes little difference.

Kevlar beads are supposed to be harder to fit but the hardest job I've had fitting tyres has been with wire. Some tyres are available in both (there's normally a little difference in the compound as well). The kevlar version is nominally more expensive, but can be cheaper if it's stocked in more competitive places. I found this with my winter tyres. As the kevlar version folds it can be cheaper to ship as well.

The weight saving of kevlar is real but small enough that you're not going to notice unless you're racing at a high level.