Surely you need to find vendors and surfing takes time as reputation check is a must. Why is that so? You offer and sell products to end-users, then you forward orders to suppliers. As for suppliers, they produce and ship the orders directly to your customers. You are a supplier for your customer as he/she doesn't know that a third part (a producer) even exists. As you do not control production and packaging, you need to prevent disputes regarding products (description match, quality) or services (package, delivery) from the side of your end-customers. Suppliers analyses include ratings and feedbacks review.
You need to make vendors investigation if only you are not using Dropwow
.This is the only dropshipping-oriented marketplace that collects only those dropshippers that meet compliance requirements, so you don't need to examine suppliers reputation as this work has been already done.