Sea Io Description

This beautiful 2020 50´ Lagoon sailing catamaran offers two large queen berths each with private ensuite baths including electric heads, vanity and separate showers. The third cabin is double midship birth that shares a head. The queen cabins and yacht both offer wonderful natural lighting and great ventilation plus fully air-conditioned depending on the guests´ desires. The salon will seat up to six guests in comfort for lounging or dining plus with numerous lounging areas, there is plenty of space for gathering as a group or finding a private place for one or two to relax. The aft exterior offers alfresco dining for up to six guests along with spacious top deck seating and lounge area in front of the helm, plus a forward lower deck lounge area behind the trampolines. TOYS: 2 Stand Up Paddle Boards, Snorkeling Gear, Tubes ,2 Sea Scooters, 2 Fishing Rods & Onshore Games. DIVING: Offered Rendezvous Only

Cruising Area of Sea Io

Pref. Pick-upAYH/RH
Other Pick-upYHG
Summer PortSt. Thomas, USVI
Summer OperationsCaribbean Virgin Islands
Winter PortSt. Thomas, USVI
Winter OperationsCaribbean Virgin Islands


Length50 Feet
Beam26.7 Feet
Draft4.7 Feet
A/C NightYes
Bimini TopYes
Children AllowedYes
Water MakerYes
Water Capacity2 x 63 gal
Ice MakerYes
Internet AccessOnboard WIFI
Turnaround48 hrs, Inquire for 24


TP in HeadsNo
Electric Heads3
Accommodation Details
NOTE: The midship double cabin is not suitable for 2 adults, only 1 adult or 2 children.

Owners/Crew currently take the Owner´s/Master Cabin.
Owners/Crew are willing to relocate from master cabin to another queen cabin for $1,500.

Suitable for up to 4-6 guests (see layout). 5th and 6th guests must be comfortable sharing a head with another guest cabin. This yacht is great for 4 pax or 6 pax families. Would also work for 3 couples if the 5th and 6th guests are comfortable sharing a head with another guest cabin.

Water Sports

Dinghy (Feet)Gala 330 center console
Dinghy Hp30
Dinghy Pax8
Sea ScootersYes
Snorkel GearYes
Standup Paddle2
Swim PlatformsYes
Boarding LadderStern and Hydraulic Dinghy Lif
Fishing GearYes
Gear TypeTrolling and Casting
Fishing Rods1
Under Water CamYes
Under Water VideoYes
Other Toys
Water Toys Include:
Two Yamaha 500Li underwater sea scooters with 2hr battery life
Two SUP (paddleboards)
Full snorkel gear (fins, masks, snorkels)
Floating tubes

GoPro and Drone to Capture vacation footage

Scuba Diving Scuba Diving Symbol

ScubaYacht offers Rendezvous Diving only
Air CompressorNot Onboard


Salon Tv/DvdYes
Salon StereoYes


Special DietsInq

Green Initiatives

Make Purified Drinking WaterYes
Re-Usable Water BottlesYes

Sea Io Crew Profile

Crew Number2
Crew SmokeNo
CaptainDavid Harkness
Chef / First Mate
Chef / First MateLillian Harkness

David Harkness
Captain Dave´s previous professional career was in Information Technology where he served as Chief Information Officer (CIO vs Sea IO) for multiple Fortune 500 companies. He gave up strategic planning, corporate politics,and 24x7x365 phone calls to pursue a life on the water with his spouse of 26 years, Lillian.

Having grown up on both coasts and several states in between, Dave lives to explore the best that each new location had to offer. He continued that quest with his own boys who for 20 years alternated the family vacations between “crazy fun” and “educational” adventures. Regardless of what you´re looking for in your charter vacation, Dave will be your perfect guide to ensure there´s something here for each and every guest.

Lillian Harkness
Similar to Dave, Lillian has held many positions in IT in several Fortune 500 and non-profit companies. When she was not stuck in the office, she loved the outdoors and is an avid runner. She completed several half-marathons, a full marathon, and several triathlons. As a child, Lillian lived in Mexico City for 14 years where she grew up enjoying the delicious and bold flavors of the country. It is the combination of these flavors, some family recipes, and the fresh ingredients of the Caribbean, that Lillian has incorporated into her menu and drink fare for you to enjoy.

Even before Dave and Lillian were married, they traveled internationally together and soon discovered a common love for the water. Owners of several watercraft and boats, they lived on a lake where they honed their water sports skills and loved hosting and entertaining their friends and family. Dave and Lillian always looked the opportunity to unwind from the rat race by planning exciting get-aways either in hot sunny spots of the Caribbean or snow skiing in New Mexico, Colorado and Utah.

Come discover and share Dave and Lillian´s love of the Caribbean on their new Lagoon 50 Catamaran.

Sea Io Calendar

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Sea Io Reservations & Port Locations

Start DateEnd DateDetails (Holds can be challenged)
Mar 29, 2023May 26, 2023Unavailable: St Thomas, USVI* to St Thomas, USVI*
May 27, 2023Jun 03, 2023Booked: Yacht Haven Grand to Yacht Haven Grand
Jun 04, 2023Oct 31, 2023Unavailable: Puerto Rico* to Puerto Rico*
Dec 30, 2023Jan 06, 2024Booked: St Thomas, USVI* to St Thomas, USVI*

Sea Io Rates / week

The prices shown are for the entire yacht for a week-long (7 nights) charter.
Low price: $18,500

High price: $22,500

Season2 Pax3 Pax4 Pax5 Pax6 Pax
2022/23 Winter$18,500$19,250$20,000$20,750$21,500
2023 Summer$18,500$19,250$20,000$20,750$21,500
2023/24 Winter$19,500$20,250$21,000$21,750$22,500
2024 Summer$19,500$20,250$21,000$21,750$22,500

Yacht terms: All Inclusive

An all-inclusive charter covers all provisioning and running expenses. This includes a captain and crew that is fully trained and committed to your safety and enjoyment of your trip. A chef will provide the kind of exceptional, personalized meal preparation that you would expect of a five-star restaurant. The listed rate may not include all local taxes, cruising permits, premium beverages and scuba activities. Inquire for more information.

Send us an inquiry to get specific pricing for Sea Io.

Sea Io Guest Reviews

January 2023

I am so thankful for having my family on such a memorable trip of a lifetime...The services, food, productions, and cleanliness was perfection! However you both will remain dear to my heart and mind! I feel like I have made new friends. Can´t wait to see you again! May God love and bless you and your family. With love and wonderful memories.

January 2023

This week was amazing! I will never forget the memories we made this week. We couldn´t have asked for better Captains and Chefs! You made our trip extra special. An extra thank you or all that you did for my babies...time of their life! Til next time…

January 2023

What a wonderful time that we will never forget! Thank you so very much! Till the next time!

Lillian and Dave Harkness were excellent hosts

“ We had a wonderful time! Lillian and Dave Harkness were excellent hosts. Lillian is a fabulous cook and exceeded our expectations at every meal. She carefully took into consideration our preferences and dislikes. Even my youngest, who is sometimes a picky eater, enjoyed her meals and drinks.

Dave prepared an itinerary that was detailed yet flexible and we were able to hit all of our ´must see´ locations and activities. They assisted with taxis on land for dinner, shopping and getting to and from the airport. They also were very helpful in arranging our necessary covid testing prior to departure.

The yacht, the Sea IO, was comfortable, clean, and ran smoothly. It had several open seating areas that accommodated the whole family for meals and games, so it felt spacious. Dave was a competent and experienced captain even in some tight spaces.

Overall, it was a great experience, and we would definitely consider it again in the future at other locations. “

Jay Bell - 03/17/21 Charter Feedback

“ Captain Dave! I’m sure you heard from Dad and Daniel, but I just wanted to personally reiterate how grateful I am for this trip. We had a lot of excitement and anticipation for our charter, but once we met you, you blew our expectations out of the water.

Yes, the beautiful bays and sublime snorkeling were a treat; Lillian’s homemade cooking were over-the-top delicious, your willingness to pass on stories and sailing expertise was unforgettable. But the best part of it all was the late night laughter and the gradual building of new friendships along the way.

You and Lillian truly have a remarkable way of making guests feel welcome and inspired to take on the adventure of sailing the seas and exploring what God’s creation has to offer. I loved learning and testing my own seaworthy skills under your direction, and I left on Sunday feeling almost sad that it went so quick.

Thank you for the great memories, and know our entire group enjoyed our time with you. We’d love to write a review or offer any feedback that would help you both as you continue to look for charters.”

Wickes Charter Feedback

“Thanks you for the truly exceptional experience! Our charter greatly exceeded all of our expectations from our accommodations, to our gourmet meals, to our activities in the water and on land. Sea IO Lagoon 50 was very well equipped with all of the toys and luxuries, was very spacious and comfortable in all the living spaces and cabins. Even the dinghy was top notch! Thank you for the vacation of a lifetime!”