I use Calgel, which is a soft gel and I always describe to clients as a 'permanent enamel'...
I hardly do extensions, if I do then it's usually on new clients who have no nails or existing clients who have broken their nails. About 99% of my clients have their own nails grown out and have NNO ( natural nail overlays) with their own nails underneath so there is no need for extensions.
I'm not sure I can help you with what I charge because what you charge depends on where you are. I see you're in Canada so maybe some of the Canadian geeks on here can help you with that.