$100k is a lot of money, but in the luxury market it can quickly evaporate.
One thing you'll need to consider is secure storage, probably dry storage, under cover for when you're not using it. A 7-8m Rib won't be cheap.
Then find yourself a broker/dealer and try a few boat options on the water. Then can get a full marine survey checking hull, engine, history, credit, etc.
Goldfish ribs would fit the bill in terms of comfort, style, capacity, with sun deck area. Something like the Goldfish 25. Even then, you might have to be flexible on budget.