Would you have any idea how much will it cost you to register a sole proprietor business in the Philippines?

As far as I know, registration fee varies per city. But just to make sure, I suggest you allocate around 5,000 pesos. I based it from these articles. Here's some further read that might be helpful for your concern. http://businessdiary.com.ph/3634/business-registration-steps-the-easy-way/ http://businessdiary.com.ph/3634/business-registration-steps-the-easy-way/

What industry would it be? I registered a sole proprietor business for an e-commerce business in 2014. I only spent around 3,700 for the business permit + around 2000 for DTI, 500 for baranggay permit and I don't recall the costs incurred for BIR. It also varies per city. If it's an actual physical store, I guess rates are way different.