So if I don't implement shared storage then I wouldn't need vMotion, correct? My understanding with vMotion (not Storage vMotion) is that in a setup with shared storage I can more VMs from one host to another and take the host offline for maintenance. But, if I don't have shared storage I can still use vMotion, but the storage is still on the host and would have to move it before I can take the host offline for maintenance, for example, correct?

Let me phrase it like this:

1. vMotion helps you with planned maintenance on a physical host (including updates, patches maintenance on its physical interconnects and whatnot) by migrating a live running VM from one physical host to another and it does not incur downtime. It will be a manual process in your case and take quite some time if you don't have shared storage, because the whole VM disk data needs to be transferred over the network. Most cluster environments use shared storage that makes vMotion a no-brainer and also enables DRS.

2. VMware HA is a cluster feature that protects you against unplanned physical hardware failure or hypervisor failure (PSOD) by restarting the VMs on different hosts of the cluster. It's automatic but the process WILL incur a short (usually application-wise 1-3m, depending on how long it takes to boot and initialize) downtime as the memory state of the VMs is lost and they undergo a complete boot cycle (basically it's as if you push the physical reset button on your server).

HA requires shared storage because the new host somehow needs to access the source VM data files if the other host has failed. Without shared storage you will first have to somehow get the data to the surviving host through backups, recovering the failed host or its disks or whatever.

It's a very manual process and can take some time for multiple VMs and you should cross fingers that you planned the disk space accordingly to put all VMs on a single host.