I’ve never stayed at finale, I stayed near genoa, was there with work, I took a drive over to finale for a mooch around, and instantly knew why it was a favourite for mountain bikers in Italy. I certainly intend on going there with wife and toddler and bike later in the year. There’s plenty on the web about the area, and plenty of good hotels at finale.
If f. L is fully booked, try further down the coast in portovenre or lerici. Both beautiful places I stayed in both. Lerici for beaches, not sure about the riding . They are both at the foothills of the Ligurian alps though and I’ve thought they look like the riding could be great. I can recommend hotels if interested.