How much is HMA maintenance fee?

Excuse me, could you kindly clarify the specifics of the HMA maintenance fee? I'm interested in knowing the exact amount or perhaps a range that I should be expecting to pay. It would be greatly appreciated if you could provide some insight into whether this fee is fixed or subject to any fluctuations, as well as any potential factors that might influence its determination. Additionally, is there a specific schedule for when this fee is charged, or is it a continuous, ongoing expense? Thank you in advance for your time and assistance.