Opening service/shop?

[ServisMobitela]

Hello to all good peoples here

Im new here so forgive me if I misplaces topic, my apologizes. I have a question and I hope that I will get many opinions as posible because its great thing to me.
Is it still profitable to open shop/service store for smartphones? There will be new, used phones for sale, all acessories needed, bumpers, batteries, hedphones etc, and ofcourse big service for phones, tablets, pc and laptops. It will have big website with webshop and blog. Every advice will be helpful and apreciated.

Thanks