Supplier consignment is a special procurement process in which the materials are stored at your premises but are still owned by the vendor. What you must do when using supplier consignment are:

Create consignment info records, which contain information about the conditions and delivery data for a consignment material from a specific vendor.

Settle liabilities resulting from consignment stock withdrawals, which means that you pay the vendor for the materials that you have consumed from the consignment stock. Reference:SAP S/4HANA Sourcing and Procurement | SAP Learning, Course S4520, Unit 4, Lesson 1.

The stock determination strategy is a set of rules that defines how the system selects a suitable stock for a material requirement. To use a stock determination strategy for a material in management, some prerequisites are needed. First, a stock determination rule must be assigned to the business transaction in Customizing. This rule specifies which stock types and special stocks are allowed for the transaction. Second, a stock determination rule must be customized and assigned to the storage type. This rule defines the sequence in which the system searches for available stock within the storage type. Third, a cross-application strategy for stock determination must be customized. This strategy determines how the system selects a storage location and a batch for the material requirement. The other options are not prerequisites, as they are optional or not related to the stock determination strategy. Reference: [SAP Help Portal], [SAP Community]

Time-dependent conditions are conditions that have different values depending on the validity period. For example, you can have different prices or discounts for different time intervals within a contract or a scheduling agreement. You can configure the usage of time-dependent conditions for these two documents in Customizing for Materials Management under Purchasing -> Conditions -> Define Price Determination Process -> Define Schema Determination -> Determine Schema for Standard Purchase Orders -> Assign Schema Group to Purchasing Organization. Reference:SAP S/4HANA Sourcing and Procurement | SAP Learning, Course S4520, Unit 5, Lesson 1.

To have MRP generate a procurement proposal for 1000 pieces for each supplier, you must maintain the following:

Set a maximum lot size in the quota arrangement item and activate the lx checkbox, which means that MRP will split the total requirement quantity according to the quota allocation and create one procurement proposal per quota arrangement item.

Set a maximum quota quantity in the quota arrangement item for each supplier, which limits the total quantity that can be procured from each supplier within a validity period. Reference:SAP S/4HANA Sourcing and Procurement | SAP Learning, Course S4525, Unit 1, Lesson 1.