Before purchasing a verified PayPal account, you have to focus on your countries IP address. Because, if you are a non-us person and if you want to buy an USA verified PayPal account then you have to Buy a VPS first. Because, if PayPal address and your IP address doesn't match then your PayPal account get limit/banned shortly.
Before buying a verified PayPal account you have to check the provider previous customers feedback. Previous customers feedback will help you to select a reputable seller/provider.
Check online reviews and testimonials from previous buyers.
Conduct online research to establish the seller's standing in the market.
Consult with friends who may have purchased accounts before.