Hi,
You may map the staff & guest SSID with different VLAN provided you have configured the backend configuration on the Switch / Router accordingly. In case ‘Inter-VLAN’ Routing is enabled on the backend Switch / Router then you may restrict the communication by applying ‘Access List’.
In case you are talking about the http / https session time-out then you may increase the value and check (maximum is 60 minutes). You may follow the below mentioned link (Page 51)…
https://www.cisco.com/c/dam/en/us/td/docs/wireless/access_point/csbap/wap371/administration/guide/1_0_0_10/1CSWAP371-SWUM100_1_0_0_10.pdf
Clustering provides a centralized method to administer and control wireless services across multiple devices. You use Single Point Setup to create a single group, or cluster, of wireless devices. After the WAP devices are clustered, you can view, deploy, configure, and secure the wireless network as a single entity. For more details you may refer the above mentioned link (Single Point Setup).