We are stuck with using heating oil which costs an arm and a leg out here so we have gone to the TOYO tankless model and it not only works great it saves us a ton of money over a boiler or traditional holding tank system that you are looking at replacing. There are some gas models that are worth looking at as well, I am guessing you have gas down there and that would be cheaper than the TOYO oil system.
Down side: Toyo systems are spendy up front bet the saving adds up fast and they are simple.
Walt
