Patricia,
Hubby and I went to Oahu in January this year. We stayed at the Queen Kapiolani Hotel for five nights (Mon to Sat.) for a room with two queen beds for under $1400.00 for the five nights. Booked through Booking.com. Our initial price there was about $2200.00, but I checked periodically after the first booking and saw a price drop, so I reserved at the new price and cancelled the first reservation. (I always book cancellable rate!) This included a discount I got from Booking.com as a frequent customer. The hotel was a short block to Waikiki Beach. Room was smallish with no coffeemaker, but the beds were comfortable and room was clean and well-tended. We walked about 2 long blocks away from the beach to catch buses to take us to various sights, using the HOLO card recommended by someone on this forum (senior rates available, unlimited use per day). We also used Lyft for evening excursions to restaurants. We did not have a view. I found in my search that a beach view really added to the cost of a room, and since we were out and about every day we didn't regret the lack of view due to the large amount of money we saved.
The floor that the pool was on had a bar/restaurant that had some happy hour specials, and we had meal there on our arrival night that was very good. We had a cocktail there almost every night (nice sunset views over the beach from this pool/bar/restaurant area).
Being 80 and 81, we didn't swim in the ocean, or do any strenuous activities, but enjoyed walking along the beach. Sights I would say to NOT miss are the Bishop Museum and the Arizona Memorial. We took the bus to and from each of these places. We also visited the Punchbowl National Veteran's Cemetery (best to use Uber or Lyft to get there) and the Friday noon musical concert at Queen Kapiolani Palace, a free treat and one of our fondest memories...chairs are provided. We walked about 1/4 to 1/2 mile from our hotel to another hotel to pick up a rental car for a day to drive to the North Shore, and stopped at many beaches to relish the scenery and views along the way.
We have been to Kauai twice and the big island once, but never Mauai, so can't offer any advice there. I will add that I love Hawaii (the big island) and would return in a heartbeat if the opportunity presented itself!
One last thing, we went to Duke's Waikiki on Thursday night for their all-you-can-eat prime rib dinner. Delicious food! Also, we celebrated a birthday at the "House Without a Key " restaurant another night. Not cheap, but delicious food. Also, the Barefoot Beach Cafe South of our hotel, right on the beach, was good, simple food with fun musical entertainment (outside eating) and a nice sunset stroll along the beach to get there from the hotel.
Have a wonderful time!