Use a custom permission set that is assigned to the user because custom permissions are a way to grant access to custom processes or functionality based on user profiles or permission sets. Custom permissions can be referenced by Apex code, validation rules, flows, or other logic to control whether a process should run for a user or not. Custom permissions can be used to declaratively control process execution by assigning them to users or profiles.

A junction object is a custom object that has two master-detail relationships with two other objects. A junction object allows administrators to create many-to-many relationships between objects, such as relating multiple accounts to multiple regions.
To create a junction object called Account Region to link the standard Account object with a custom object called Region, an administrator needs to do the following steps:
A) Make a master-detail relationship field on the junction object to the Region object.
A master-detail relationship field is a field that links a child record to a parent record. The child record inherits the sharing and security settings of the parent record. By making a master-detail relationship field on the junction object to the Region object, an administrator can link each Account Region record to one Region record and make Region the first master of the junction object. Reference: https://help.salesforce.com/s/articleView?id=sf.relationships_considerations.htm&type=5 D) Configure a master-detail relationship field on the junction object to the Account object.
By configuring a master-detail relationship field on the junction object to the Account object, an administrator can link each Account Region record to one Account record and make Account the second master of the junction object. This allows administrators to relate multiple accounts to multiple regions through the junction object. Reference: https://help.salesforce.com/s/articleView?id=sf.relationships_considerations.htm&type=5

As explained in question 4, record types allow administrators to offer different business processes, picklist values, and page layouts to different users based on their profiles. By using separate record types for rental and real estate opportunities, DreamHouse Realty can capture different client information on their opportunities using custom page layouts for each record type. The record types can also determine which sales processes and paths are available for each opportunity type. References: https://help.salesforce.com/s
/articleView?id=sf.customize_recordtype.htm&type=5