SaaS app new feature

I am looking for a company, which has experience with SaaS applications. We need help with project in Laravel with adding new functionalities for our users. The application is for sharing photos among family members. The application is written in Laravel and js. We need to secure it against simultaneous logging in of members to the same account. In case if user tries to log in and someone else is already on the account, there will appear an appropriate message and the user can decide if he wants to log out the other user or log in himself.
At the same time, there will be an email sent with a proposal to upgrade the account to a higher package. If the user buys the higher package, more users will be able to log in to the account (according to the price list).
In case you have any more questions, please ask them in your offer.