build high availability infrastructure for E-commerce SAAS

hello freelancers ,

i have SAAS app in e-commerce, every client can build his own online store without any previous experience , i want to build high availability system for it .

our app uses Laravel every client have his own store have his own custom domain and subdomain


our app is deployed now in VPS with Cpanel and this is our Cpanel problems :
1- we can't scale with Cpanel
2- we can't handle unlimited custom domains
3- our app based on 1 server so if our server goes down all of our clients goes down

currently our app does not have any traffic or clients
i want to make this system high available , so it can handle a lot of traffic without any problem also i can scale it later without problem

challenges :
1- handle many traffic at same time .
2- keep our app performing better .
3- can scale simply .
4- handle clients custom domains and subdomains with ssl
5- make our app secure against DDOS.
6- achieving high availability
7- keeping our server costs low as possible for this system


1- we will discuss all other details over chat before start
2-the freelancer who can do this project will be our server admin (long term freelance work)
3- please don't bid if you can't achieve this above challenges