Would you please check if they or someone they know that they have any Magento integration experiences following area:
1) Backend integration with any ERP system.
2) Any 3rd party integration:
a. Login integration such as Amazon, Google, Facebook login.
b. Payment integration such as Authrize.net, Paypal, Visa, Amazon (new)
c. Shipping integration such as USPS and UPS or DHL
3) Drop shipping management
4) B2B or any supply management integration.