If you have low water pressure then you’ll want to run a booster pump.
Even with a pump and good pressure it takes ages to produce pure water, 50% of the water processed goes down the drain and the other 50% is your pure water, not ideal if your on a water meter. then you’ll want somewhere to store this water, some sort of tank with a float valve or something that you can keep filled until you need it. Then filter in the cost of replacement pre filters every 6 months, chlorine will destroy ro membranes
Alternatively you could just soften your water a bit and take away the chlorine with something like this
You could even go so far as to put it on your mains in and treat the whole house to some clean water, it won’t be as pure as ro water but will be much better than tap water and much more cost effective.
I use this for drinking water
And also run a 40/40 ro for work so got access to pure water but it’s too much work for my liking, just turn on the tap and out comes water is what I like for my plants, I don’t have time to mess around with pure water for gardening, each to their own though