SYS: Sell Your Stuff

- Modeling a System that Helps Sell

Used Goods

Authors:Fang Gao

Stephen KhouSungmin Lee

Advisor:Dr. Michael Carchidi

Group 9

Demonstrations:April 23, 2009

RCA Lab, 11:00 – 12:00 PM

02:00 – 03:00 PM

Department of Electrical and Systems Engineering

Introduction

Source: 100 Samples per Zone Distance, Collected on 12/7/04, 12/17/04, 1/19/05, 1/26/05, 4/8/05

Results and Conclusion

Software Architecture

System Overview

Many students and faculties of the UPenn community trash their used items when many of these items are still in “more than desirable” conditions. The owners of these items would most likely rather sell these items to make some additional income than simply toss them away. However, because of reasons such as the lack of experience or the time commitments associated with these sales, members of the UPenn community have continued to discard quality items. Thus, the objective is to model a potential establishment that will effectively mitigate the entire selling process by eliminating the seller’s need to research and monitor transactions.

Based on our vision of how this establishment will operate, a mathematical model was created to simulate yearly operations. Data of demand (what students are willing to buy), supply (what students are willing to sell), costs, and other variables associated with maintaining a business was also gathered and analyzed. These empirical data were processed by our business model to determine if such a business was sustainable.

Revenue and Cost Inputs

Employee costs are the primary costs associated with long term sustainability. Item cost is unique in that it is not an attribute we can actively reduce as it is directly tied with revenue. In addition, it is potentially possible to create incentives for students to store their own used-items (supply), avoiding warehouse costs. If supply and demand remain relatively consistent in future years, should the business operate as a typical buy-warehouse-sell establishment, the business is sustainable under current conditions (real world data). However, this is highly contingent on the choice of items to sell. In our study, the items were carefully selected based on their attributes (selling price, quantity, supply, demand) in an attempt to minimize costs. Overall, the book selling prices is the most sensitive, mainly due to the fact that there are a significantly larger supply and demand of books. In terms of the additional profit that can be generated by the selling of an additional item, the most sensitive was the desk/table category. Independence was generally assumed.

IntermediaryStudent

Want to Sell

Research/Offer Data/Quote a

Price

Sell

Revenue

General Flow

Where this establishment idea lies in the

flow

Revenue

$/Good (Price)

# of Goods

Actual (from Housing)

Estimated (from Survey)

Used-goods Market

Cost

Time

$/time-person

# of People

Storage

Overhead

Employee

Goods

Transporting

Utilities

Server & Webspace

# of Goods

$/Good

Storage Cap

# of Goods Stored

# of Warehouses

$/Warehouse

# of Vehicles

$/Vehicle

$/Mile (vehicle specific)

Miles/Gal

$/Gal

Profit

Employee Wage (67.4%) Transportation (0.2%)Warehouse Rent (21.0%)Overhead (11.4%)

Data Input

Warehouse Algorithm

Transportation Algorithm

Decision Algorithms

Result Algorithms

How much to take in?

How much to store?

How much was sold?

How much is left?

Items

Quantity

Demand

Warehouse Cap

Vehicle Cap

Etc

Statistics and Data Output

iniDatabase

Database Prime

Employee Wage (7.5%) Transportation (0.0%)Warehouse Rent (2.3%)Item Cost (88.9%)Overhead (1.3%)

The “intermediary” box represents the SYS system which helps students sell their used goods. Selling at the highest possible price is achieved by the experiences and superior market knowledge. When the item is sold, part of the revenue would go to SYS to compensate any cost generated by the service. The rest of all the revenue would be awarded to clients.

Table (3.9%) Couch (11.4%)Lamp (1.1%) Chair (1.9%)Audio Sys. (5.0%) Textbook (76.8%)

Cost Contribution (with Item Cost)

Cost Contribution

Revenue Contribution

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