Recommendation (short): For a multi-hour audiobook that sounds like you, use a cloud custom-voice workflow (ElevenLabs or similar) but plan for iterative recording, careful editing, secure storage, and a rights/license check before distribution. Aim for 30–60+ minutes of high-quality, varied speech as a realistic minimum for a close clone; more if you need very fine-grained expressive control.

Why this works: Modern TTS models give great timbre and intelligibility from tens of minutes of clean audio; extra data improves naturalness, reduces artifacts, and helps match expressive dynamics across chapters.

Decision criteria (pick what matters most):
- Fidelity needed: hobby narration vs near-indistinguishable audiobook. Higher fidelity -> more samples (45–120+ min), more iteration, higher cost.
- Budget: hobby/indie (<$50–$300) vs professional ($300–$2k+ for repeated cloning, licensing, and post-production).
- Privacy comfort: cloud-based cloning is easiest but stores voice data with the provider; choose providers with explicit voice ownership/licensing and secure storage.
- Technical skill / workflow stage: if you can record clean takes and do basic editing, you can iterate quickly; teams needing full production may want an audio engineer.
- Platform rules: some retailers/publishers restrict synthetic narration—confirm before publishing.

Sample requirements (practical):
- Minimum: 15–30 minutes for a passable clone; recommended: 30–60+ minutes for audiobook-quality.
- Format: WAV, 44.1 or 48 kHz, 16-bit+ (prefer 24-bit), mono, consistent mic distance.
- Content: read natural prose, dialogs, short sentences, exclamations, questions, and emotionally varied lines; include problem phonemes (names, acronyms, uncommon words).
- Style coverage: capture both neutral narration and a few expressive paragraphs to teach prosody.

Recording + editing tips:
- Record in a quiet, treated room; use a decent condenser or dynamic mic and pop filter.
- Don’t apply heavy EQ/compression; upload dry takes. Do light click/pop removal and gentle noise reduction only if necessary.
- Break into many labeled files (by paragraph/chapter) rather than one huge file.
- Iterate: generate test clips, note mispronunciations or odd prosody, record extra targeted samples for trouble spots.
- Post-process generated audio: gentle EQ, de-essing, light compression, breath removal, and consistent loudness (e.g., -18 to -16 LUFS for audiobooks). Save originals.

Distribution & legal risks:
- Voice ownership: ensure the provider’s terms grant you a usable license for commercial audiobook distribution. Keep written proof.
- Platform policies: check Audible/ACX and other stores—some require disclosure or ban synthetic narration; verify before publishing.
- Privacy: don’t include sensitive PII in training files; secure uploads & backups.
- Misuse/claims: keep consent docs (you if it’s your voice; releases if an actor).

Best-for / Avoid-if:
- Best-for: authors narrating their own books, indie producers, iterative small-batch releases.
- Avoid-if: You need absolute silence of artifacts or immediate publisher acceptance without checking TOS.

Practical checklist (copyable):
1) Choose provider and confirm licensing terms (commercial use, redistribution).
2) Record 30–60+ min varied samples, WAV 44/48kHz mono, 24-bit if possible.
3) Clean minimally, split files, label clearly.
4) Upload, create custom voice, generate test samples.
5) Iterate: add targeted samples for errors and re-train if available.
6) Post-process TTS output to audiobook loudness and style.
7) Securely store originals and license docs; verify marketplace policies before publishing.

If you want, I can list a short sample script to record (phoneme coverage + emotional lines) and a prioritized set of 20–30 lines to capture the most useful material for cloning.