I would caution you about tankless water heaters unless you have totally familiarized yourself with the pros and cons. There are issues with them that you may realize only after living with it if you don't take the time to find out before. Lots of people complain about capacity, the common complaint is that the manufacturers numbers are way biased and not based on real world uses. Capacity may be great for taking a shower, but add the dishwasher going on, or the kids taking a shower at the same time... system failure. Adding the real capacity usually makes the system too expensive. Break down usually also comes up as an issue with people talking about having to wait 1-2 weeks for a replacement part. 1-2 weeks without hot water? Hot water tanks are a tried and true idiot proof system that is gallon per gallon cheaper when you take real life circumstances in to consideration. You can also get a replacement installed the same day. When they break they go gradually, when tankless breaks it is like throwing a switch.
Just some thoughts, I hope you fully understand the pros and cons so if you do decide to go tankless you go into it with both eyes wide open.