We rarely use the term "deep clean", and there is a reason: every cleaning we do is a full one. What people usually call a deep clean is our standard cleaning plus add-ons — the oven inside for 319 CZK, the extractor hood for 319 CZK, windows at 199 CZK each, emptying and wiping the cupboards inside. You order exactly what you need instead of a package you will half use.
It is a different matter when nobody has cleaned the flat for years, nobody has lived in it, or something has happened. That cannot be priced by the number of rooms, because the condition decides, not the size. It is agreed individually and usually charged by the hour at 319 CZK.
Describe the condition in the order note, ideally with a photo of the kitchen and bathroom. Then we set aside enough time in advance instead of stretching the appointment on site. In rented flats around the ZČU campus in Bory this is standard practice at every change of tenant.