When it comes to choosing a username for an expert in group buying, it's a good idea to come up with something catchy and memorable. Here are a few suggestions for an English username for a group buying expert:

1. DealHound: This username suggests someone who is always on the hunt for the best deals and discounts.

2. BargainMaster: This username conveys expertise in finding and negotiating the best bargains and discounts.

3. GroupBuyGuru: This username positions you as an expert in navigating and organizing group buying deals.

4. SavvyShopper: This username implies a keen understanding of shopping strategies and finding the best discounts.

5. DiscountDynamo: This username suggests an individual who is knowledgeable about obtaining and sharing discount information.

6. VoucherWhiz: This username implies expertise in using and finding vouchers and coupons for group purchases.

7. BulkBuyExpert: This username suggests proficiency in coordinating and managing bulk purchases for savings.

8. CouponSleuth: This username implies skill in discovering and utilizing coupons for group buying discounts.

9. DiscountMaven: This username positions you as someone who is knowledgeable and experienced in securing the best discounts.

10. ThriftyTrader: This username suggests expertise in trading and leveraging group buying deals to maximize savings.

Remember, whatever username you choose, it is important to ensure that it accurately represents your expertise in the field of group buying and appeals to your target audience.

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When it comes to choosing an English nickname for a group buying enthusiast, creativity and personal taste are key. A well-chosen nickname can reflect your personality, interests, and expertise in the world of group buying. Here are a few tips to help you come up with an inspiring English nickname:

1. Reflect your expertise: As a group buying expert, your nickname could showcase your deep knowledge of the industry. Consider names like "DealMaster," "SavvyShopper," "GroupBuyGuru," or "BargainHunter."

2. Highlight your passion: If you have a strong passion for group buying and consider yourself a dedicated advocate, try nicknames like "DealDevotee," "GroupBuyEnthusiast," or "DiscountFreak."

3. Emphasize your skills: If you are especially skilled at finding the best deals and leading successful group purchases, choose a nickname that showcases your abilities. Examples include "DealWhiz," "GroupBuyPro," or "DiscountDynamo."

4. Showcase your personality: Your nickname can also reflect your unique personality traits. If you are known for being outgoing and social, consider names like "GroupBuySocialite," "DealChatter," or "SocialShopper."

5. Be creative and original: Stand out from the crowd by choosing a creative and memorable nickname. Combine words or play with puns to create a unique name. For example, "DealNinja," "Buyzilla," or "CouponCrafter."

Remember, the most important thing is to choose a nickname that resonates with you and feels authentic. Test out several options with friends and see which one best represents you as a group buying expert.