Sales Order - Setup fee and monthly fee

Hi Community,
with great pleasure and joy i am evaluating ERPNext and try to find ways to design our processes in ERPNext.
I am currently stumbling across the following challenge, which i did not find a full answer for yet.

We are selling to our customers hardware and services. Both can come with a one-off fee/one-time installation fee and a monthly service fee.

I did understand that for one-off fee items, “Quotation” and “sales order” would perfectly fit our requirements
As well i did understand that for monthly fees, “Subscription” would fit quite perfect with the auto-generation of “Sales invoices”.

But how do i connect both together to one “Sales order” or should “contract” come into play here?

I imagine presenting our customer one document with a full overview of all items, including their one-off and their monthly fee.

I understand i can customize the “Sales Order” Doctype to include a link field for a “Subscription”, but the data like “costs” of “Subscription plan” and “Qty” of “Subscription plan details” would not be showing on the “Sales order” for example when printing.

Maybe one of you already found a clever way i did not see yet, as i would imagine we are not the first with one-off and monthly fee items.

Any hint would be much appreciated.

Thanks in advance,
Stephan