Just because a hotel is up for sale doesn't mean that its owners are about to go bankrupt. The Barcelo group is a big chain and the chain is not up for sale, only a very small number of its hotels.
This means that the hotel group as a whole is viable and it is the hotel group and not the specific hotel which guarantees your accommodation. You can usually tell when a company is about to go bust. I recall that just before the Royal Sun folded, accommodation was being offered at desperately low prices. But if you check out prices for holidays at the Santiago and Varadero hotels with the major holiday companies, the prices quoted are quite competitive. The major holiday companies which are ABTA approved are still accepting bookings and they are very careful about their reputations so there is no immediate problem.
From memory, I recall reading many months ago that about 20 % or more of Tenerife's hotels were up for sale, yet none of them has folded. So don't worry.
When the Royal Sun went bust, its customers were transferred to the Playa Arena Hotel and most were more than satisfied with the alternative accommodation. If you are still worried then check your travel insurance and maybe for peace of mind pay a few pounds more for additional cover.
You are very lucky to be staying at the Barcelo Santiago. First class hotel. Wish I had your problem.
However, you said that the prices for May were similar to Christmas. This seems exceptionally high for May. Personally, if I were you and could back out without penalty then I would do so purely on price and look for all inclusive late deals for the Playa Arena and the Costa Los Gigantes hotels on the Thomson and First Choice websites. They look exceptionally competitive at the moment. Hope they are not in trouble!
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