Hi,
First of all, please check the price for this project. The estimated date of delivery is 15-20 days. You should provide WHM/CPanel admin access. Landing should be checked with new or old accounts from both hotmail/outlook and Gmail but finally should be with Glockapps or any other tools to check the landing and if gmail and hotmail/outlook accounts are all green with inbox landing, the project should be considered done. So before you assign this job, you must send 2/3 emails from the affected sending domain to either Glockapps or similar spam testing tool and provide snapshot here and then after the work you need to check again.
Thank you!
Probal Rahman