How long should one test skincare products in order  to develop product sufficiently?

How to start a skincare brand                                                                                                                                   What should one know when you start a skincare business?
Where can one find chemical engineering people to make your skincare products for example Korea, Japan, Thailand
How much should one have to start a skincare business?
Costs of testing and making ingredients with chemical engineering?
How long should one be testing skincare products until its verified?
Voluntary people to use the skincare products? If the product is helping them or not? How long should they be testing the products on their bodies and faces to see improvement?
How long should one test skincare products in order  to develop product sufficiently?
What kind of resources should one be looking at when  starting a skincare?
For instance if you make your skin care products in Korea, what laws and regulations should you follow to make your skin care legal world wide shipping?
What are the risks of making your skincare products in public?
How likely can one get sued for skin care business?
What kind of prosecuted charges happened in the past for the skin care businesses that affected the company?
Show examples of skincare businesses that got sued for their products and why and what do you think they should have done better?
how likely can a skincare business benefit?
When your products are officially approved by testing what are the further steps for your skincare business?
How much of skin care products needed to test selling? To not risk so much on money on skincare products?
How to promote skincare products online?
Website?
Shipping?
Collecting customer data?
how to promote your skin products in Sephora, ultra-beauty, Nordstrom…etc
Is feedback on skincare important for customers and business?
How much money will you be getting in a skincare business?
Is skincare more of a trend than makeup industry?
How to know when to lunch your next product of skincare?