It is best to do a price comparison of other hair extensionists in your area then decide how much you would like to charge.. you don't want to overprice yourself or underprice yourself. Practice on your dummy head or family tobsee how long it will take you to fit a full head...all those methods are pretty similar application so are likely to pretty much all take similar times
Be careful not to price to low at the start and if you need practice try doing this in family and close friends first rather than giving services free/very reduced to the public.
I would price what your model client will be more than willing to pay for. Then market your brand towards them.
It's all good looking at what others charge. However you have to take into consideration of who their model clients are, price of the hair they are providing, time it takes to complete etc... I really wouldn't worry about what others charge in your area, you will be surprised at how many people will travel from across the country, even the world to get a good hair extensions tech!
Hone on in with who your ideal clientele are. What lifestyles they live, how much they earn, where they live etc... really narrow it down to that one person and exact age. From there, have a limited offer. For example 10 first people to book for an introductory offer at £... With the introductory offer use this to really practise speed, customer service, techniques etc... after that, you should have enough confidence in hair extensions to put your prices back to normal. Everything you do I.e advertising and marketing, please make sure it fits to this ideal model client, and you will have no issues with what to charge.
In my opinion, there is no such thing as being over priced. If people think you are too expensive, then that means your brand is marketed towards the wrong groups of people. If your service is on point, they will be people who will pay and more!
Think of it as like Gucci and Prada. They are not fussed about what other people charge for bags, apparel etc... they are in a league of their own. They tailor to their target market and keep standards high and exclusive. The same can be done with hair extensions. Wish you the best of luck! Xx