If you want to use a good quality foam cannon like an MTM hydro type which creates thick shaving cream like foam, then you need a min of 130 bar with 1.8 Gallon/min or around 7 litres/min pressure washer. These will cost you anything between 16k (Chinese) to 35k (karcher k4)
Agar Tau sirf tez Pani k mazay leinay (and no foam cannon) Tau go for any 12-16k Chinese one 110ish bar/1500 psi type k. Total, ingco, Bosch etc. If you're from Lahore, go to branderth road to buy one or just buy a bit expensive one (same brands) from an online listing