In my case, see what's available on jet2holidays, then google the name of the accommodation and see what it costs to book separately, also if there's any comparable alternatives and also price up the flights.
We like to be fairly central and not drive on holiday so are particular about finding accommodation that is in walking distance of restaurants, supermarket, transport links, beach etc, so obviously that's a limiting factor.
Hotels tend to cost more per night than apartments, so in your example, you're not really comparing like with like. If you looked on Easyjet for a one bed apartment or studio, you might find the price gap closes significantly.
Plus if you want to stay in two different places, you usually can't do that as part of a 'standard' package so to get that as a package, you're looking at the more specialist/high end/travel consultant model, which is likely to be more expensive.