A679-Switzerland1985 FDC Bern “1885-1985 Bäcker / Boulanger” 50 Helvetia stamp

Title:
Switzerland 1985 FDC Bern “1885-1985 Bäcker / Boulanger” 50 Helvetia stamp on special cover (Swiss Baker-Patronage) – Ausgabetag 10.9.85
Category:
Collectables → Stamps → Europe → Switzerland
Condition:
– First Day Cover (FDC) envelope, franked with the 50 Helvetia issue (1985) and cancelled 10 September 1985 “3000 Bern” special postmark.
– Very good condition: the envelope appears clean, cancellation clear, and the design features intact. Some light age-toning possible (please inspect photos).
– Not mint stamp alone: mounted on cover with cancellation and commemorative embossing.
Item specifics:
Country/Region of Manufacture: Switzerland
Year of Issue: 1985
Denomination: 50 Helvetia
Stamp Type: Commemorative
Cover Type: First Day Cover (FDC)
Cancel Date: 10.9.1985
Cancellation Location: Bern (3000), Switzerland
Theme: Baker / Baking trade (1885-1985)
Included: Envelope with embossing (association logo), special post-mark, and stamp.
Mint / Used: Used (on cover)
Presence of gum: Not applicable (on cover)
Certification: None stated
Additional Notes: Rare thematic item aimed at baking/pastry trade; contrast to common general issues.
Valuation & Recommended Price:
Based on available market data: In the listing of mint annual sets from Switzerland, the 1985 year-set in mint never hinged condition is listed at about CHF 23 for the annual compilation (per Wieland Briefmarkenversand). 
Given that your item is a special FDC (which may add collect-value) but is used on cover (thus less value than mint unused stamp set) I would estimate a retail (Buy It Now) price of around £15–£20 (British Pounds) as a realistic market level.
Recommended listing price: £19.95
Auction (starting bid) option: £9.95 or £12.50 to attract bidders.
Recommended Listing Format:
– Format: “Buy It Now” at £19.95, and also include an option “or Best Offer” (to allow negotiation).
– Additionally include an Auction variant: Start £9.95, no reserve, or low reserve around £12.50 for 7-10 day duration.
Suggested shipping & handling details:
– Shipping from UK: Postage by Royal Mail (e.g., 1st Class or International) with tracking, due to collectible nature.
– Packaging: Use protective plastic sleeve + board backing + padded envelope to protect cover from bending.
– Shipping to overseas: Clearly state international shipping and any customs duties might apply.
Listing description (sample):
> For sale is a beautiful 1985 Swiss First Day Cover issued 10 September 1985 in Bern (3000) to mark the 100-year anniversary 1885-1985 of the Swiss Bakers & Pastry-Chefs Association (Association Suisse des Patrons Boulangers-Pâtissiers / Schweizerischer Bäcker-Konditorenmeister-Verband). The 50 Helvetia commemorative stamp is affixed and cancelled with the special “Ausgabetag 10.9.85” postmark. The cover also features the embossed logo of the association and is in very good clean condition. A great item for the thematic collector of baking/trade stamps, Switzerland philately or FDC covers.
Please inspect the photos for condition details—light age-toning may be present but there are no major faults noted.