Wow what a lovely place - beats mine to shame! So modern and everything I could see for a beach family holiday. And you are going to the trouble of providing bikes etc so you are willing to do all the maintenance etc. Well done you on great super host rating!
I can see you are making your property more appealing all year around given spa and firepit so you have that covered. They seem to be what people seek in winter. Are you planning to increase price to cover that, given the maintenance on it?
As to the other host comment, is this a location no one actually visits in off months? What's the competitors doing? Is there a tourism bureau , I'd have a chat to the staff and get their thoughts as well (if you are not living local?). I agree price is the biggest draw for off peak. Definitely agree with min 2 night booking, probably not worth it for 1 night.
Not sure how you price, but are pricing per guest? Could you attract just a couple or a few people because the larger the house, the harder it is to get bookings (I'm in the same position, I take 12). Is there a way of sectioning off some of the area/bathrooms/bedrooms to make it available for less than 2 families? Larger properties need more time in advance for families to book. Its just a fact. The smaller the property the easier to get bookings.
Because of my house configuration, I was able to section off wings of my property and have them as separate listings, which I pitch separately (one for older family, one for younger family due to what is on offer/available in those wings). And then I priced per guest so it kept the base rate really cheap with a token cleaning fee on top (whereas my full house i price per house and no cleaning fee). It took me awhile to get this pricing right with competitors in the region for a family of 5 or a couple with a baby, but it's working. I'm now getting more occupancy, and worked out a calendar sync. Because its base bottom more competitive pricing, these 'half house' listings of mine don't get the full service white glove treatment I offer the full house bookings to keep my costs down. ie no guest hamper valued $150RRP (just a bottle of wine and a token biscuits/chocolate), no added value stuff I do for the full house bookings. They have to turn on the water themselves, get everything going themself. Results so far, 5 star ratings mostly because most guests realise they are getting a very big amazing property for basically the price of a hotel room. And I'm getting more bookings in off season too as a result.
You might not need to set separate listings like I did depending upon what you already off(but it is interesting experiement and doesn't cost anymore to do). Could you provide 1 bathroom, all common areas, 1 or 2 bedrooms only depending upon # guests. Perhaps the spa, extra beach gear etc is all locked up too. That's an optional extra charge.
Hope this helps!
Kind regs MK