This is permissible but it is best to ask Allah Paradise and seek refuge in Him from hell without such specifications and details.

Could I make a dua to Allah swt and ask Him to grant me such n such a reward in the hereafter for example hoor ayn or a river or a ship for doing a specific good deed?? Because Allah has told us to do business with Him. And the concern is not the dunya rather it’s building up a good place in jannah.