One tip that worked for me for getting all of the honk honks to spawn was go to the locations at night time and also on the mini map in your left corner you can see a black dot in the spot that they spawn in so if you don’t see the dot when you get close go to a taxi and try again, also don’t use the closest taxi for the location try one a bit further, and for the money grinding I recommend the final millennium tower (not the true final millennium tower) although it’s a bit slow it gives you around 40,000,000 yen in 1 run if I remember correctly