A604-Royal Mail First Day Cover “A Celebration of Anniversaries” 1989 4 Stamps

Title:
Royal Mail First Day Cover “A Celebration of Anniversaries” 1989 – 4 Stamps on Cover
Category:
Collectables → Stamps & Postal History → Stamp Covers / First Day Covers
Condition:
Good used condition. The cover shows minor ageing/spots (see images) but the stamps and cancellation appear intact and clearly readable (“First Day of Issue 11 April 1989 Edinburgh”). The FDC has been opened on the reverse flap but remains complete.
Item Specifics:
Country/Region of Manufacture: United Kingdom
Year of Issue: 1989
Set Name: A Celebration of Anniversaries
Format: First Day Cover (FDC)
Number of Stamps: 4 (se-tenant pairs)
Cancel: First Day of Issue 11 April 1989, Edinburgh
Condition Description: Cover has minor foxing/staining marks visible near flap and edges; stamps remain fine and mounted.
Certification: Not separately certified.
Additional Info: Produced by The House of Questa (indicated on reverse flap).
Valuation & Recommended Price:
Based on recent listings and catalogues for similar UK 1989 FDCs, typical market value appears modest. For example, a listing of the same set shows a asking price in the low pounds. 
Given the condition and desirability, a conservative valuation would be £8-£12.
Recommended eBay Listing Price:
£14.99 (Buy It Now) – this gives a little margin above valuation while remaining realistic for collectors.
Auction Option:
Start at £7.99 with no reserve, or reserve at £10, to attract bidding interest and give flexibility for sale.
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