Does the price ever fluctuate?

Yes. The price of ArDrive uploads can fluctuate based on the computing power available to the Arweave network at any one time. We anticipate that these fluctuations should even out as the Arweave network increases in scope. Arweave is currently in a time of rapid growth with a 23x increase in the amount of data stored on it year over year.

There are a few factors that cause fluctuations in the price, such as the price movement of the AR token, but the network adjusts storage costs dynamically to keep costs predictable. 

So you can be confident that even as the price fluctuates that you are still paying roughly the same amount for permanent storage.