Requirements for HA and storage

[Pepe]

Greetings guys!
This is my situation, im trying to install this with HA, it works but our VMware is almost out of space and im searching a solution for NAS as storage, but i read is not the best solution for this.
Im setting up this for around 200+ accounts, the migration takes almost 300GB of data. On the other hand, can i use a desktop for this purpose? If thats the case what are the requirements for HA? I mean, the two machines will be always on.
Thank you, have a good day!