One faulty opening, rather than a whole-house project
If most of your Rhymney glazing is working as you want, a single problem should not automatically become a complete replacement brief. Make a note of the affected opening and separate the glass condition from the frame movement and locking action. A pane that looks cloudy between its surfaces is a different concern from moisture on the room-facing surface. Tell the team where you see the problem and when it appears. Replacement glass and lock or hinge repairs are services in their own right; whether either is suitable depends on the existing unit.
An entrance that needs to work every day
A front door has to fit the way people actually enter and leave your property. Before choosing a new composite or uPVC door, think about which side it opens from, where coats or furniture sit and how much privacy you want through any glazing. If the current door is difficult to close, say whether you are mainly seeking a repair or already want a new appearance. Avoid forcing a sticking lock to demonstrate the fault. A clear description is more useful than taking a mechanism apart.
Several improvements at the same address
Replacing a door and a nearby window together can raise questions about matching finishes and sightlines. Give your Rhymney enquiry one clear list of the openings involved, rather than assuming every room needs the same product. A kitchen window, front entrance and garden-facing opening may each have different priorities. If other building work is planned, explain how it relates to the glazing and who is managing it. The quote should concern an agreed scope, not an assumption that unrelated alterations are included.