In order to find a high-quality wholesale hair supplier, you may need to do more research. Some things are listed below for your reference:
Look for Reviews on YouTube.

Before looking for a new vendor, Check their social media profiles, and watch several review videos on YouTube. Try to find the most unbiased video to get the most unbiased insight.

Look for Reviews with Pictures. 

You will get a better idea of what the hair actually looks like, in case there are some great customers who post pictures with their reviews.

Buy Unprocessed Hair. 

Try to purchase hair that is as close to its natural state as possible, because Ombre hair or bleached hair can be risky.Orders and Reviews. 

You can try to buy your hair from a vendor who has completed at least 300 orders and has a high rating of 93% or higher.

Content and Service. 

Check out if they provide customer service whether by phone or email with quick communication by reading the about pages. Generally speaking, you can trust the vendor if their store has high-quality content and service.

Delivery Time.

Ask how soon will you receive the hair.
Return Policy. 

A return policy indicates that the vendor is confident in their products. If for some reason you’re dissatisfied, they allow you to return the hair for a full refund (minus shipping) as long as you do not make any changes or tampering with your hair. In this way, you can buy with confidence.

Opening Years. 

It’s also important to see how long they’ve been in business.