Using MRP to create demand for BOM materials to move from one sloc to another

We are designing a consignment kit build-to-stock system and we want to use as much vanilla SAP functionality as possible. The consignment model requires live tracking of bundled finished goods as kits while in the field, meaning that we cant use normal production functionality to produce a single finished good in inventory. We also need to ensure that all of the kit parts are inside the same parent material (its a dedicated container) before shipping, so we cant use the sales order to determine where to pull the parts from. We have a non SAP CR< and an AS400 warehousing system.

Kits and their parts have their own storage locations, CHCK and CHAK, separate from other finished goods slocs in the same plant. We have four core slocs for differentiating inventory: CD01, BP01, AD01, and CA01. We already have external procurement set up for some materials in the plant, which pulls them into AD01. This complicates setting up any kind of MRP solution to pull inventory into a different sloc.

When kit is returned from consignment, the Warehouse receives the kit parent material into stock, then confirms the children of the parent match what is on the return order (parent material is listed as Higher Level item line on the return order), and the children are then received into stock.

If a part is bad or missing during receipt, we need to replace that part with another from finished goods stock. We want to create demand for the part to be pulled from finished goods into the kits sloc automatically. We think that the best way to do this is to have SAP somehow review the children in inventory under the parent against the parent's BOM, and create an STO to pull any missing parts from the appropriate sloc in the plant. This is the build to stock aspect of the system.

Its more complicated than that though. Which sloc to pull the child material from depends on where the parent is stocked, CHCK or CHAK, and that values of two material characteristics of the child material. This is important because the same material may be stocked in any of the four other slocs, and the material must be pulled from the right one.

Any help on generating demand into a specific sloc would be great. Thanks!