Thank you very much for your kind words!
In this case I believe the best solution would be to use 3 separate search instances instead of one. One for each category – accomodation, to rent and for sale. They can be exactly the same, but each one configured to search exactly that one category, and of course the different price range.
Then I would place each search shortcode one into some kind of tab shortcode (each one into different tab panels), and the labels would be the categories (for sale, to rent, accomodation). Then clicking on the tab labels would switch the search engines visible, thus solving the issue.
I'm not sure if your theme has some kind of tab with labels solution, but that should not be too hard to create. Visual editors usually have one, and some themes as well.
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