Spain Beach Family Vacation

Avoid Southern Spain in August unless you like near Saharan heat.

But from Barcelona to French border is Costa Brava a very nice in summer. Checkout The hotel Parador Aiguablava one of the most amazing locations to stay on Costa Brava.

Thanks @sbrodhead about the warning about the temps in Southern Spain that is a good point and narrows down our search.

Spain and Greece will be very hot in August but it’s also peak season and expensive. I’ve looked up the Windjammer and it is a luxury resort. I’m not sure you’ll get an apartment in a hotel similar for your budget, in August, anywhere in Europe.

Sani in Halkidiki, Greece has the type of accommodation you like and it’s definitely luxury but it’s also very expensive.

Mallorca or Ibiza would probably fit the bill for a location.

I really like Alicante as a beach destination but it won’t have as many upscale resorts.

For a combination of mountains and beaches then I would consider Port de Pollensa in Mallorca. There are some nice beaches there amid a pleasant fishing village with the backdrop of the Unesco listed Tramuntana mountains where the delightful towns of Soller, Deia and Valdemossa are located.

For luxury villas you might be interested in https://www.villaspollensa.com/holidays-villas-for-rent-mallorca/. Be advised that in August you'll be looking at a minimum of €10,000 per week.

I don't think you'll find something similar to the resort you stayed at in St Lucia, accommodation tends to be either hotels or villas rather than a combination of both. You might consider Marriott's Son Antem resort which is where we stay regularly. The accommodation consists of two and three bedroom villas with a shared pool between every eight villas which can be very quiet (we've had the pool to ourselves on a number of occasions) and there's a larger central pool along with a spa, restaurant, gym etc which is more lively. It's not on the coast however but the nearest beach is around a 20 minute drive and the mountains can be reached in 40 minutes. The rates in August are around €500 a night for a two bedroom villa.

As an idea, I looked up the price of a villa at Costa Navarino, a luxury resort in Greece, and got a price back of €47,000 for a week in August!

Thank you all for the advice. Clearly that $1,000 per night budget won't work with any Hotel Villa options in August in Greece or Spain. I am considering a shorter 3-4 day at a Airbnb in Casta Brava a 1-2 day stay in Barcelona and then a 2-3 day stay in Paris. Kids want a more urban experience for some reason. In Barcelona and Paris we will have Marriott Hotel options where I have points I can use.

I might be able to help if you clarify a few things:

Are you looking for a hotel in which the rooms are in individual villas? How about if it was a great beach resort hotel but rooms were not separated into villas?
Do you need a private plunge pool on your balcony/terrace, or in the villa?

If you can narrow down the beach areas in Spain that you are considering, it might be easier.
For example, there is a brand new Fairmont resort on the Costa del Sol, with private villas.

https://www.fairmont.com/en/hotels/san-roque/fairmont-la-hacienda-costa-del-sol.html

Are you a golfer?
Must it be ON a beach, or is a nearby beach ok?
Do you plan to rent a car?

FINCA CORTESIN is among one of the most upscale hotels in Spain; its not on the beach but they have a shuttle to their beach club, nearby; it's on the Conde Nast "Gold List" if that means anything to you:

https://www.cntraveler.com/hotels/casares/finca-cortesin

If this it the type of hotel you are interested in, I can offer a few more ideas.
Andalucia has mountains, beaches, hills, beautiful "white" villages, and fantastic food.

If you are willing to consider Sicily, there are. few options I can think of on that island that might suit you.

And there are many hotels on the various coasts of mainland Italy.