above vs over to talk about amount of money

Solution 1:

Licensing references for the usages are quite hard to find.

Lexico gives under above:

• (adverb) 1 [the part of speech is disputed by others]

• 1.1 Higher in grade or rank.

an officer of the rank of superintendent or above

(this sense, for grades / ranks, is not available with 'over')

• 1.2 Higher than a specified amount, rate, or norm.

boats of 31 ft. or above

And, under over, Collins gives:

(adverb) ...

• more; in excess; beyond

three hours or over

So with numbers, or especially, as here, with measures (numbers + units), either is acceptable. Cambridge Dictionary ... Grammar is saying that with pure numbers and numbers with standard units or non-physical 'units' like people, cars, outside the 'or over/above usage, , 'over' is the more usual choice . 'There were over 50 000 deaths from the virus.' But the examples it scores through (I get above sixty emails a day. / If you weigh above 100 kilograms, then you may need to start a diet.) are just less usual (and more formal in register), by no means unacceptable.

And as @Isabel points out, more (and where necessary more than) may be the most idiomatic choice. 'They spent £160,000 or more on toys, CDs, and perfume.'