We have 6 kids and had my adult son and his wife living with us. So all In all we had 9 people 2 dogs and a lizard in this house.

I Installed it myself converting from a 40 gallon tank heater. I would not say it was a breeze but it also wasn't that bad. To be fair I am a mechanical engineer and am handy around the house. I would not recommend this as a DIY if you have problems with IKEA furniture. You will need to understand vent sizing calculations to determine if you need a 3" or 2" vent. Depending on where you put it you will need to be comfortable punching holes in the exterior of your house and installing the vent and intake in an appropriate manner to not cause a hazard. I had to run 3/4" gas lines as well because the old heater had 1/2" gas lines. (Don't try and get by with a smaller line even if your neighbor said you can). Also as an FYI make sure you have a 3/4" full bore valve. Lots of gas line valves say 3/4" but only have a 1/2" bore on the ball valve. This will create a restriction in flow and cause you to throttle your gas flow unintentionally potentially causing issues in the combustion chamber during high gas demand times.

All in all it was worth it. Before purchasing I would recommend having the system fully thought out.
1. Gas flow - do you have 3/4" or larger gas lines you can tap into. What parts will you need to get the gas line to where you need it (valves, tees, reducers, flex line, fittings"¦)
2. Venting and intake - where will you vent the PVC pipe out of the space. (Do not vent into galvanized pipe it will corrode out and damage your house) you will need to maintain drainage of the exhaust line condensed gasses. How many elbows and tees will you need, 3" or 2" pipe or are you using the 2 in one pipe.
3. Venting and intake out of the house - there are safe configuration and unsafe configuration of how to exhaust the gasses out of your house. You also need to consider how to get clean intake air in. Don't kill your family with CO because you were too cheap to design your system correctly.
4. Drainage - this system will require a drainage system for the condensed gasses to drip down. During peak operation this can be a substantial amount of liquid.
5. Power - you will need a GFI protected 110V outlet close to the mounting location.

Do your homework and do it right and it will go smoothly. If you can't do it right then hire someone to do it.

I got a quote from a local plumber to remove a tank and install a tankless water heater but it was more cost effective to purchase this unit and have it installed. The same company agreed to charge labor only and installed this unit. Buying this unit and paying for installation only saved me a least $1,500 off their initial quote. It took them the better part of a day but it works great and I am happy with my switch to a tankless unit.

And further saving on costs, my gas company gave me a nice rebate, I got a tax credit when I filed my taxes, and I'm supposed to also get a rebate from Rinnai (they are stalling and definitely take quite a long time with lots of follow-up.)

The only downside of this tankless heater is that in the winter, it takes about 15-30 seconds longer for hot water to get to two floors above the unit (it is in the basement.) Sometimes the temperature slightly fluctuates a bit but it's not a big deal to me. Overall happy with my purchase and hopefull it will last a long time - just have to flush it at least once a year (soft water in my region.)

Before purchasing a "tankless heater" I did my research. While some were less expensive, they didn't have Stainless heat exchangers or were less efficient and not STAR certified. This unit is easily installed IF you have some knowledge of plumbing. NOTE: Rannai and other's will NOT guarantee the unit if it isn't installed by a plumber certified by their prospective companies. I wasn't concerned by this as I am already 73 y/o and longevity isn't a concern. This unit uses very little propane. (less than 10%) in 8 months. It delivers hot water within minutes and stays hot throughout the shower. Also, being STAR certified, most propane companies issue a $150 rebate plus, you can get a tax credit when filing taxes. I cannot see a negative installing a tankless heater.

The install was pretty straightforward and we have had zero issues with the unit.

It does take a little longer for hot water to get to the area its needed but our is also further away from where the old hot water heater was.

My first tankless water heater and the directions was great. Still tweaking things added a recirculating pump. This model ru160in was not equipped with one. But for my home size this works just fine. Love the warranty it has