I tend to buy a ratchet set. Get a screwdriver type ratchet (and the perpendicular ones are handy in tight spaces) - and with those two ratchets just get an entire bit set.
Costs more than a screwdriver, but what you end up with is an interchangeable screwdriver and additional tool for tight spaces which hopefully should be adaptable to any situation. Should only cost about £30 aswell if you find something cheap but has a wide range of bits.
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