There is a $100 (in HNS) fee to stake a name in the Namebase Registry. This fee is non-refundable and will be deducted immediately from your account upon staking. This fee will cover one domain's staking costs.
If your account balance has less than the required HNS, your name will not be staked until you buy or deposit enough HNS to cover the staking fee.
The Namebase Registry charges $1 for each year of SLD registration. If a domain is registered or renewed for 5 years, the fee would be $5. You can read more about how this fee affects your payouts in this article: