This reference to the Frequently Asked Questions gives some idea of the Partsouq business model:
PartSouq Auto Parts Around the World - https://partsouq.com/en/faq-13.html
This map depicts the worldwide Partsouq customer base:
We are group of professionals, who is interested in providing the first-class service of supply chain Auto Spare Parts - All over the world!
partsouq.com
This reference gives the name, physical address, e-mail address, phone & fax numbers, and picture of the location of the business:
PartSouq Auto Parts Around the World - https://partsouq.com/site/contact
None of this gives any guarantees but it does provide some indication of a business which can be traced. This gives more confidence than many other suppliers, especially those eBay, Amazon and other suppliers who do not disclose such details.
It is very important to read and be comfortable with the Partsouq "Terms and Conditions" and "Policies" on which Partsouq conducts its business. In particular, it is important to be aware of conditions relating to Buyer responsibility for identification of Parts and correct Part Numbers, what happens if Parts are to be returned or a refund claimed, and what happens if Partsouq can fulfill only a portion of an order, etc, etc. These are not unusual conditions but it is all "buyer beware" stuff -- which the Buyer accepts by placing an order. See --
PartSouq Auto Parts Around the World - https://partsouq.com/en/terms-2.html
Partsouq discusses OEM versus Aftermarket Parts at this reference:
Our Articles
partsouq.com
All good stuff, but as with any customer-facing outfit, reputation and ongoing business has to be underwritten by enduring customer satisfaction. Threads like this on IH8MUD are an excellent source of information on the reputation and performance of Partsouq (or any supplier). Continuing posts by IH8MUD Members as customers about their experiences is a very good thing.
I continue to use Partsouq when local Toyota Dealers cannot supply at reasonable prices and in reasonable timeframes. Over several years of purchases, I have had no issues with quality of parts nor any concerns about parts not being genuine OEM as claimed by Partsouq.
Delivery arrangements have been fine and very quick (days not weeks), in my case through DHL. Sometimes (not always), Import Duty and Goods & Service Tax have been levied on arrival and managed by DHL for high value items, but that is a specific matter required by the Australian Government in my case, nothing to do with Partsouq. Other countries will have their own rules and taxes. It does mean that care is necessary when making local and overseas price comparisons. Foreign Exchange rates also can be an issue.