**4. Conclusions**

There is an abundance of EOQ models based on Wilson's formulation. Although differing in purpose, application type, or calculation principles and providing quite precise predictions for a demand per selected time interval, all these models contain the same drawback. Being based on a logic of calculating costs per one order and multiplying it by number of orders, they all fail to meet the current needs of business environments in order to be applied in practice.

We propose the modification of EOQ based on a different calculation technique which shows significant savings in warehouses costs under particular conditions.

From the proposed models, the most significant savings were observed using the 2nd variation of the first proposed model and accounted for approximately 2% of all inventory costs. The highest potential for application in practice shows the first and second variations of a fourth model due to the ability to cope with the most uncontrolled variables as the retail sector is characterized by constant shifts in demand and supply which are reflected in prices in a nonlinear manner [52]. The savings in this case would amount to 0.4% when the price of stored goods increases under particular conditions (first variation of a fourth model) and to 1.3% when price decreases (second variation of a fourth model) under researched conditions.

The limitations of our proposed models are comprised of delivery costs and price for goods to be described by uniform trend. Thus, in the future, the model could be extended to investigate the inventory management where exogenous parameters do not follow any uniform trend.

**Author Contributions:** Conceptualization, T.N. and J.P.; methodology, T.N. and M.M.; formal analysis, T.N. and A.V.; resources, D.S. and T.B.; writing—original draft preparation, T.N., A.V., and M.M.; writing—review and editing, T.B. and D.S. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research received no external funding.

**Conflicts of Interest:** The authors declare no conflict of interest.
