Virtual server. A good and plentiful minimum resources cost around 10 euros per month (expect if prices have increased e.g. due to the widespread increase in the prices of equipment components). Hourly billing is used. Many variations in resources and network topology. Hosted by Hetzner, with a data center in e.g. Finland, but it’s not strictly necessary to use their services. There is no guarantee that virtual servers will be available at any given time, which may affect, e.g. subsequent changes to the network topology.
Extra disk space. This can be expanded up to 10 terabytes, but initially only a modest 10 GB will be bought together with the virtual server and which costs 0.72 euros per month, and may not actually be needed for anything.
Domain name. This can be purchased from Hetzner, but also from anywhere else. The most important thing is that some has rights and ability to make minor changes to the domain’s DNS settings, as the domain must be set to direct to the numerical IP address where the virtual server is located.
CDN service (Content Delivery Network). A separate user account is registered with the Bunny CDN and a team member having "Manage zones" permissions should be added so that settings could be set on the customer's behalf. An advance payment of a few euros may be sufficient to last for a long time.
SSL certificate. Previously, this was purchased separately, but currently a Let's Encrypt certificate is used without cost and which is automatically renewed, which means that it doesn't require any effort from a customer. It is possible to use commercial SSL certificates, which will cause the server to perform "about a minute's worth of work" if the customer can provide the information needed to create the certificate.
For both Hetzner and Bunny CDN services, the easiest way to pay is by prepayments, which in the case of Hetzner increases the "credit balance" that is automatically used to pay the invoices.
The customer does not need to provide their bank details to the developer/seller of the publishing application. Instead the prepayments are made by sending a prepayment using PayPal's internal money transfering, after which the full amount of the prepayment is manually transferred to Hetzner and Bunny CDN.
The PayPal money transfer is preferred, especially in the initial phase, but in the later phases the Hetzner prepayment can also be paid by bank transfer. When making the transfer, the Hetzner user account's id code is entered in the reference data so that the amount sent is directed to the correct user account. It may not be necessary to pay the Bunny CDN prepayment at all for a long period of time, or even regularly if it is not used much. Bunny CDN also has other services available for use, for which a customer can choose to pay from the same prepayments.
If requested separately, the customer can receive a copy of a monthly invoice, but this is a manual operation, so sending a copy of each invoice might not happen.
Hetzner charges for the use of virtual servers, even if they are shut down. If they are completely removed, leaving only the user account for use, billing will stop immediately after the current hour.
Domain names are typically those that are renewed or not renewed annually. A purchased domain name is usually the customer’s property, and it can be transfered to a registrar other than the one from which it was purchased, but it is, of course, worth reading the terms and conditions.
Using of the Bunny CDN can be terminated at any time, but of course it is not advisable to terminate it while all other essentials are still in use.
Hetzner invoices its services on a monthly basis (or less frequently, if the total amount is below the limit it has set). The monthly billing dates remain the same, but would vary on a client-by-client basis. The first payment reminder for the first invoices will probably be sent 5 days after receipt of the invoice, for subsequent invoices probably after 10 days.
In Hetzner's case, the advance payment is intended to cover the costs for the next 30 days. If it starts to appear that the prepayment may not be paid, the customer of the web application will be contacted and it is anticipated that all Hetzner services used by the customer might have to be deactivated. This may mean that the virtual server with all its data may be deleted and after that it cannot be restored.
At least in the case of Hetzner, prepayments can be refunded for the remaining amount (minus the balance of the last invoice). According to the information received from Hetzner's customer service, the refund will be made using the payment method originally used to make the payments, i.e. PayPal payments via the publishing application developer to the PayPal account and bank transfers directly to the bank account of the publishing application customer. It is not quite clear whether there is a service fee for a bank transfer when paying back prepayments, but in the SEPA (Single Euro Payments Area) it should not be very much.
Overage costs means additional fees over allotted usage limits. In the case of Hetzner's virtual server, it means that virtual server's outbound data traffic is free up to 20 terabytes and after that customer will get charged based on overage pricing, which in Hetzner's case is 1,26 eur per terabyte (in the summer of 2026). It is explained in the writing A word about limiting data transfer costs and visitor traffic how the admin user can manage and visualise outbound data transfers.
Resources such as disk space, memory/performance for server equipment are available on request. As minimum resources, 8 GB memory and 4 vCPUs (processor time slots) have been considered as suitable, which at 14.8.2026 pricing means a maximum cost of 10,65 eur per month (at Hetzner's). Then, a virtual server will be in use, i.e. the processor is used by multiple Hetzner's client. Dedicated servers, i.e. servers used by only a single customer, are more expensive. A publishing application can be distributed over several servers, as explained in the writing about network topology changeability. Additional note: Cost-Optimised virtual servers have not always been available from Hetzner, so other providers have also been glanced through.
There are no separate agreements with Hetzner or Bunny CDN to remain their user. They just simply are excellent in terms of pricing, functionality, features and willingness to evolve. The similar permanence of maintainability is also an important criterion for using them.
The control of the Hetzner user account remains solely with the developer/seller. The reasons for this include the need to authenticate with an identity document to obtain them and the risk of making incorrect configurations. With Bunny CDN customers can make technical changes themselves or create a team member account with limited permissions to make these changes. Various optionalities can be utilitized at the customer's request without any extra charge, provided that they are not too burdensome to implement. E.g. Bunny Storage, which is another service of Bunny, could be useful.
The publishing application is not yet sold as a business, but as a private person, so at this stage the customer does not pay extra for product development, maintenance, etc.
Bank transfer is a quick operation (Hetzner specific example) -->