301a and 301b lab

I'll ping boneyard to give you a few pointers on that. He's one of the guys who has cleared all certifications.

In regards to my own lab, I use a cluster of 3 units to test riskier changes and complex setups for my clients. 2-unit cluster will likely be enough but make sure you test Active-Active, not just Active-Standby to better understand how traffic-groups work. From what I've heard, HA related questions are plentiful in LTM exam agenda.

I'm a daily Linux user. For my personal lab, I use Libvirt KVM for BigIP deployments (3x VMs), native instances of Apache web servers (covers all needs for LTM testing), and a Wordpress instance that I use as attack and exploit target (ASM WAF testing). You can do the same on Windows 10 with Hyper-V.