They have replaced it with a UHET model called the Stealth (0.8USD / 3l) - which has a 37.5% reduction in water consumption, but a 20% reduction in MAP testing results (scored a rating of 800).  

You can say you will just bill back to the residents, but that's not always feasible in some markets and we know that total water consumption decreases 30+% when residents are responsible for actual amount used not just a fixed bill back.

Will you have on premise consumption?   

I subscribe to a philosophy that may resonate with many on the forum:1) Your Primary Residence: Consumption, not investment. 

Velocity is not there right now...Just the other day I saw some data some place which was alluding to the fact that the common wisdom that lower gas prices which translate in spendable cash would result in higher consumption seems to be wrong - most consumers are retrenching!

For a deeper look see the NBER report: The Causes of Japan's "Lost Decade": The Role of Household Consumption which if you change the dates and names would be the story of what's happening here since 2008.

the 2nd association it resonates is the highly consumption-driven society we live in. in my area (coastal, urban southern california) i'm surrounded by 2 distinct lifestyles. there's the majority: seems like 95% of the local population who are renters, driving luxury cars, sporting fancy clothes, jewelry, hairdos, etc but obviously living paycheck to paycheck as exemplified by hardly a day somebody or the other is spotted  getting their car repo'ed by a camera crew. the rarer are the landlords, who in this area seem to be of mostly asian demographics (chinese, koreans, japanese) who live obviously very frugally: old 80s model sedan, oldfashion business cloths, always eating simple meal from home, seemingly never splurging $$$ other than into expanding their portfolio), my observance is relatively very few landlords in the area own relatively huge portfolios, each.with the advent of these infomercials and the internet (ie, BP) more and more people want to get a 'piece of the REI pie' and more power to them. there does seem to be this dream of rags to riches and while its ok to dream, do most people actually expect their life to turn around like that, as portrayed in most of the infomercials or even in the everyday setting where the masses living paycheck to paycheck, are spending their last expendable dollars not on depositing into savings acount, but blowing $20 on scratchies etc. in summary, is my observation reminds me of my days when i worked on wall st and the 'ra trace' was so obvious with dime a dozen stock brokers makin 6fig salaries at some point but blowing it on recreational drugs apparently costing thousands of dollars a pop to the point the next week they are broke again and that $ wasnt invested but wasted.  

In contrast, your 20-year old, gas heaters most likely have an efficiency between 60 and 75.If you do the math, you will likely find that if your existing water heaters run for another 5 years, the difference in fuel consumption to a new heater would pay a considerable amount of the acquisition and installation cost for a new heater.   

In your own home, the bulbs, particularly the replacements for halogen (GU-10, PHAR-20, etc) are a must - massive reduction in energy consumption and waste heat.In our rentals, we've moved towards using LED fixtures w/o bulbs {students will finger the LED bulbs just as readily as any other}.  

Have you tried looking into capital type projects that will help reduce energy consumption (LED light fixtures for example)?