Need new wasterwater plant, how to reduce flow

Weird topic, but I will need to replace an aged wasterwater plant. about 35 homes on this property are 1980 or older and 20 are early 1990’s and the rest late 1990’s

we all know how that the biggest user and waster of water in these homes are the old large resevoir toilets and leaky toilets…one leaky toilet can equal 18000 gals a year multiply that by 2 toilets per home and 70 units … worse case scenario I know but .that’s a potential 2.5 million additonal gals of water processed through my system each year

.I’m thinking of replacing the toilets on the homes I have for sale with an American Standard 1.28 gal “water wise” flush toilets that I have found for $128. at Lowes…as well as future units I have for sale.

That would only take care of about 20% of the park

Is there any real advantage to taking such a proactive stand in getting my property to be water wise, if so, what would you recommend for the additional 80% of the tenants homes?

Since I am paying for the water due to my operation of the well, would I be out of line going into homes and inspecting for leaks and inefficiencies?

and what would you offer as incentives to get these homeowners to repair and replace their toilets…do you know of any rebates available?