Great — here are well-located hotel options in Mumbai grouped by neighbourhood (best for solo sightseeing), with a quick note why each is handy and a source you can check:

Colaba / Gateway of India (best for walking to major South Mumbai sights)

• The Taj Mahal Palace — classic luxury, right next to the Gateway of India and Colaba attractions (ideal if you want to be in the heart of tourist South Mumbai). (en.wikipedia.org)
• Hotel Suba Palace — budget/mid-range, a few minutes’ walk to the Gateway, Colaba Causeway shops and cafes (good value and extremely walkable). (travelocity.com)
• The Gordon House Hotel — boutique/mid-range in Colaba, close to Gateway, museums and cafés (comfortable, central base). (ghhotel.com)
• Abode Bombay — small boutique hotel in Kala Ghoda/Colaba area, excellent for art galleries, museums and cafes within walking distance. (abodeboutiquehotels.com)

Marine Drive / Nariman Point / Churchgate (great for evening strolls, museums, good transport links)

• The Oberoi, Nariman Point — luxury, sea/Marine Drive views; easy access to Kala Ghoda, Marine Drive promenade and Churchgate. (oberoihotels.com)
• InterContinental (Marine Drive) — sea-facing, right on Marine Drive; walkable to Fort/Kala Ghoda and close to Churchgate/Marine Lines stations. (ihg.com)
• Hotel Marine Plaza — sea-facing, mid/upper-mid category on Marine Drive (good sunset views and easy access to south-Mumbai sights). (hotelmarineplaza.com)

Fort / Kala Ghoda (heritage, museums, galleries — very walkable)

• Residency Hotel Fort — solid budget/mid option in the Fort heritage precinct (close to Chhatrapati Shivaji Maharaj Vastu Sangrahalaya, CSMT and Horniman Circle). Good value base for solo explorers. (residencyhotel.com)

Bandra (beaches, Bandstand, Bandra Fort, cafes — different, more local/suburban vibe)

• Taj Lands End (Bandra) — luxury on Bandstand/Land’s End; great if you want seaside walks at Bandra Bandstand and easy access to Bandra’s cafés and nightlife. Note: it’s farther from South Mumbai attractions (you’ll need a drive). (trip.com)

Quick practical tips for solo sightseeing in Mumbai

• For walkable sightseeing and easy tourist access, South Mumbai (Colaba, Kala Ghoda, Marine Drive, Fort) is the most convenient base. (See hotel/area pages above for distances.) (en.wikipedia.org)
• Local suburban trains are extremely crowded at peak times — many solo travellers prefer taxis or app-based cabs (Ola/Uber/Rapido) for comfort and safety, especially with luggage or at night. Plan for slower journeys in monsoon season. (specials.indianexpress.com)
• General safety: keep valuables secure, avoid isolated areas late at night, use app-based or hotel-arranged taxis after dark, and follow local travel-advice guidance. (Authoritative travel-advice and safety guidance here.) (gov.uk)

If you’d like, I can:

• narrow these to a specific budget (luxury / mid / budget), or
• check current availability and sample nightly rates for particular dates.

Which would you prefer?