Self-custody configurations for an individual vary depending on the balance between security, convenience, and the value and frequency of asset transfers. Below are three potential configurations, ranging from a basic setup to a more complex, robust arrangement. Each provides varying levels of protection and accessibility for both high-value, low-frequency assets and low-value, high-frequency assets.

1. Basic Starter Configuration:
The most straightforward self-custody setup involves having two key wallets: a hardware wallet and a mobile wallet. The hardware wallet is used to store high-value assets that are rarely transferred (cold storage), while the mobile wallet is designed for frequent transactions involving lower-value assets (hot storage). Each wallet generates a unique seed phrase, which must be backed up independently from the devices themselves. These seed phrases are critical for recovery if the hardware or mobile wallet is lost or compromised. This configuration is simple but effective for individuals who want basic self-custody with a division between security and convenience.

2. Enhanced Secure Configuration:
A more secure approach involves adding redundancy and additional layers of protection. In this setup, the individual has two hardware wallets, which are replicas (both wallets use the same seed phrase), a mobile wallet, and a multi-signature wallet.

The multi-signature wallet operates with a 2/2 threshold, meaning both signatures are required to approve a transaction. One signer is the mobile wallet, and the second is either of the two hardware wallet replicas. High-value, low-frequency assets can be stored either on the hardware wallet or the multi-signature wallet, while low-value, high-frequency assets remain on the mobile wallet.

Each wallet has a separate seed phrase, backed up independently from the three devices. If one hardware wallet is lost, the replica or its seed phrase can recover it. If the mobile wallet is lost, it can be recovered using its unique seed phrase. This setup ensures both redundancy and security for high-value assets while maintaining convenience for day-to-day transactions.

3. Most Robust Configuration:
The most comprehensive and resilient self-custody setup involves two independent hardware wallets, a mobile wallet, and a multi-signature wallet with advanced recovery options. Each wallet has its own unique seed phrase, which is stored separately from the devices.

In this configuration, the multi-signature wallet uses a 2/3 threshold signature scheme. The mobile wallet is one of the signers, with the two hardware wallets serving as the other signers. High-value, low-frequency assets can be stored on the multi-signature wallet or on one of the hardware wallets, while low-value, high-frequency assets are managed through the mobile wallet.

For enhanced security, Shamir Secret Sharing is used to split each wallet’s recovery information across devices. This means that if one wallet is lost, the seed phrase can be used to recover it, or the Shamir Secret Shares from the other two devices can help in the recovery process. Additionally, the multi-signature wallet allows recovery via the remaining two wallets, offering multiple layers of redundancy and flexibility. This configuration is the most secure and resilient but requires more time and effort to manage and set up.

Biometric Authentication:

In any of these configurations, the hardware or mobile wallets can incorporate biometric authentication, such as fingerprint or facial recognition, to enhance ease of use without compromising security. This ensures that while self-custody configurations remain robust, accessing assets can still be quick and convenient for the individual.

Each configuration offers varying degrees of security and flexibility, allowing the individual to select the best option based on their needs, ensuring they maintain complete control over their assets at all times.