Look at any hobby in your life and break out the money spent vs the enjoyment you got out of it.
For example the Cinema costs me £10 and a film is 2 hours long, meaning my fun time costs £5 per hour.
A £100 console would have to provide me 20 hours entertainment for it to be comparable to going to the cinema.
These days any PS4 game will have 10-40 hours content, but buying them costs money. Popping on CEX website the most expensive PS4 games are £12. Assuning you only get 10 hours of fun from a game...
The question you should ask yourself is are there 3 games on the PS4 you are interested in playing?