customization of magento marketplace shipping and wallet/store credit for website -- 2

Need Magento freelancer for below Requirments:- 1. Customization of marketplace shipping (currently only seller can add shipping carrier in ours defult marketplace extension , need to customize for admin can add shipping carrier for markplace like delhivery etc.) 2. Set up Wallet / store credit for website to deposite refunds from customer so that customer can do shopping from his avialable balance in Wallet of website , Customer can also check his available balance in his profile or account. 3. Need Improvement for speed of website and loding time. Thanks Ajay