information about licensing and patching SSAS

I have one server for data warehousing, and it has 2 instances of SSAS (SQL SERVER Analysis Services). The data warehouses are not that big, less that 200GB, and I backup the whole thing on a daily basis. Now they have asked me to patch\upgrade it: > Thank you yes, this indicates it is a 2016 SP1. The reason I ask is > that, as I indicated on Friday, when we tested the creation of > measures (e.g. year-to-date net applications) in Power BI from a live > connection to your Analysis Server, this caused unexpected errors. Our > research shows that this is very probably caused by your Analysis > Server version, and the solution is to install a Cumulative Update > (CU) 3 for SQL Server 2016 SP1 , or a more recent CU (as you can see in > the list on the left of the page, these go up to CU 11). As far as we > know these are free to download, but you may need to ask your > consultants for help. I wish I had different servers for LIVE and TEST environments. Where can I find information about the costs of licensing involved for a small server just to run a SSAS instance? I am talking about a simple, single, machine, with windows server 2012 R2 and the latest ssas. Also, patching for SSAS is anyhow different from sql server? I find licensing costs a tricky topic sometimes, with not-so-clear or contradictory information around.