Property sales business is a business activity of buying and selling goods and services related to property (buildings and land). Business in the property sector is a type of business that is quite promising. With the increasing number of competitors in this property business, developers must be more active and innovative in introducing products, so a solution is needed to attract many buyers by using an e-commerce system. The problems faced in this sales system are still in a less broad scope, data management still uses a handwritten media system on a sheet of paper so it takes a long time, and monthly report storage media still uses a ledger that requires accuracy. The designed system produces fast, precise, and accurate information in the entire process, both in terms of data input, transaction processing (orders), to output. The development method used is a prototype model and the PHP programming language so that the website runs dynamically which is supported by a MySQL database. The solution obtained from the above problems is to build a website-based online sales system, so that sellers and buyers do not meet face-to-face. With this system, it is expected to expand the area and facilitate sales marketing and increase and make it easier for the public to get information.

PT Oni Utama Suskes is a company engaged in electrical mechanical contractors, bridge construction, village roads, clean water assistance to produce onipanel, onilite, onitray. Problems that often occur in systems that are running are processing incoming goods data, outgoing goods data, and making stock reports only recorded on a piece of paper then copied back using Microsoft Excel software then printed and submitted to the company leadership, so that sometimes they experience problems and difficulties. in calculating goods and the information provided sometimes does not match the availability of existing goods, and the data is not integrated into a system so that the company's performance is slow. From the problems encountered, the researchers used the UML (unified modeling language) method which describes the inventory system that runs at PT Oni Utama Sukses, so a web prototype for incoming goods, outgoing goods and inventory reports was made to computerized and integrated warehousing activities. to accelerate company performance. especially in warehousing. Based on the description above, this report analyzes the inventory of goods to make it easier to obtain and issue information that will provide a better inventory system for PT Oni Utama Sukses