There more users you have the bigger the impact on the users is when your solution is down. In addition you should start calculation how many users your company has. But if you want to create a good managable solution in Power Platform you should use Dataverse as your datasource, cause it is creatable and patchable in your PowerPlatform solutions. With Power Platform you could do this implementations without the external company. You want to build a business application and you let a company implement an Webapplication or an App and some automation hosted in Azure. What is your plan? What is the background? You can also take a look at the offical licensing guide, there you can see what the licenses are capable of:

On the other hand when you have a couple of workers who want to creat some simple automations or Power Apps that connect the standard Microsoft stuff (like SP and so on) you can think about it. If you want to have clean solutions with a nice ALM (Application Lifecycle Management) you cannot work with the basic version. If you really need it depends on where you are standing, what do you want to achieve and how clean your solutions should be. You can read this article here it describes why you should use the premium licenses if you want to want to use the Power Platform professionally: Power Platform – How to start right? ♥ PowerCorner ()

So if you are working in a company that really wants to make it right you will need to have the premium licenses. When you want to use other datasources like Dataverse or an SQL Server you will need to have the premium licenses or use the LogicApps. Honestly the basic versions are good enough to make your automations work as long as you store your data inside the SharePoint, Outlook or Onedrive. I think you are describing the basic version which is included into the enterprise licenses (E1, E3 and E5).

Hi is no real 'free version' of Power Automate.

Power automate desktop free