Okay, I need to create a professional and useful wiki document "업셀링" (ups) under the categories of 경제 (Economy), 시장 및 비즈니스 (Market and Business), 마케팅 전략 (Marketing). Let me start by what upselling is From what I know, upselling is a sales technique where a seller encourages a customer to purchase a more expensive item, an upgrade, or add-on products to generate more revenue. It's commonly used in various industries like retail, hospitality, technology, etc.

First, the document structure should have a clear title (H1), an overview/introduction section, several detailed sections (H2, H3), and a references or related documents section. The content needs to be accurate, objective, with appropriate depth and breadth. The language should be easy to read, and any technical terms should be explained.

Starting with the title, it's given as "업셀링" so that's straightforward. The overview should introduce what upselling is, its purpose, and its relevance in marketing strategies. Maybe compare it with cross-selling to clarify the difference.

Next, the detailed sections. Let me think of possible H2 sections. Perhaps:

1. 업셀링의 정의와 개념 (Definition and Concept)
2. 업셀링의 목적과 효과 (Purpose and Effects)
3. 업셀링 전략의 유형 (Types of Upselling Strategies)
4. 업셀링 적용 사례 (Case Examples)
5. 업셀링의 주의사항 (Considerations)
6. 관련 개념 및 차이점 (Related Concepts and Differences)

For each H2, I need to break down into H3s. For example, under Types, I can have product-based, service-based, experience-based upselling. In Case Examples, maybe retail, technology, hospitality industries. Also, in Considerations, discuss ethical aspects and customer experience.

I should ensure that each section provides enough depth. For instance, in the Definition section, explain how upselling differs from cross-selling. In Purpose and Effects, talk about increasing revenue, customer satisfaction, etc. Maybe include statistics if possible, but since I might not have exact data, keep it general.

Use bullet points or tables where appropriate. For example, a table comparing upselling vs cross-selling. Also, code blocks might not be necessary here unless there's a technical example, but probably not. Use emphasis like bold or italics for key terms.

Need to maintain a professional tone but keep explanations clear. Avoid overly complex terms without explanation. Make sure the document is at least 800 characters, but given the structure, it should be longer.

Check for any possible mistakes. For example, confusing upselling with cross-selling. Make sure to clarify that upselling is about upgrading the current product, while cross-selling is about buying additional products.

Also, think about examples in different industries. Like in restaurants, suggesting a premium wine (upselling) vs suggesting an appetizer (cross-selling). In tech, upgrading to a higher storage phone model (upselling) vs buying a case or accessories (cross-selling).

In the strategies section, maybe discuss techniques like personalized recommendations, limited-time offers, bundling, etc. Each of these can be a subsection.

In the case examples, provide specific scenarios. For instance, Apple encouraging customers to buy a MacBook Pro instead of Air, or a hotel offering a room upgrade.

In considerations, mention the importance of not being pushy, understanding customer needs, and maintaining trust.

Finally, the references or related documents section can link to related marketing concepts like cross-selling, customer relationship management (CRM), sales funnel, etc.

Let me start drafting each section with these points in mind. Make sure the flow is logical, from definition to application to considerations. Use clear examples to illustrate points. Avoid redundancy and ensure each section adds value.