I did this very thing 5 years ago (with our first child being born in the 3rd month of construction). It was a monumental task! I did nearly all of the work, but hired a few subs for the things I didn't want to spend time on, such as drywall (hate it) and electrical (can do it to code, but would take me at least twice as long).
I remember being in your shoes before our build. I spent countless hours drawing, looking on plans online, checking out local houses, etc. I ended up coming to a decision on the rough sq footage of the house, then narrowed my search from there. Eventually I found an existing plan from a "kit" place in British Columbia, who mostly built smaller pre-cut cabins, but this was their new, biggest plan at the time. They would supply materials (uncut) and plans for most of their offerings. I didn't go with them, as they are 3000+ miles from me, but I ended up working out a deal to buy their plan following some modifications to it.
Our actual build took 9 months from breaking ground to move in one week before
, with me working what felt like 800 hours a week on it, on top of working FT most of the way through at my real job. Oh yeah, having a baby in the middle of there made things a little busier, too. Needless to say, it was the most exhausting but fulfilling year of my life. We had a few minor setbacks along the way, as would be expected, but nothing major enough to make me not want to do it again. I want to build a vacation home next, where we're not waiting to move in the day it's "done".
A few basic things I can tell you from my experience are:
-You'll probably find something wrong with any plan you find, so look for the one that has the most "right" about it and try to modify as you see fit.
-As it's been said, see if you can walk through homes you might like. Being able to put yourself inside a plan is a lot harder than walking through a real structure.
-Not sure what your budget is like, but K.I.S.S. if need be. Standard building tips like keeping lengths in multiples of lumber available (2', 4', etc) increases efficiency
-Look at plans for use of space and wasted space. I feel that we ended up with a design having almost no wasted space. This gave us the most house for our $
-Look at plans for smaller houses and consider future expansion if the costs don't work out to your favor to build bigger now. I planned ours so one side would be easy to add onto with a great view if we ever felt it was necessary. 3.5 years later we had twins (bringing us to 3 kids, one beyond our "planned" 2) so we would like to rearrange bedrooms and add a new master on the back of the house, with a nice wooded view.
-If you do end up building, try to put your $ into the things that are hardest to upgrade later. We put radiant in our basement floor (& throughout house), used better windows, insulated very well, etc. These are things we wouldn't regret later and would be difficult and expense to replace, too.
I could go on, but there are a lot of things to consider if you really want to get into it. Feel free to ask any questions you may have. I found that starting with nothing was hardest. Not knowing what to build, how much to put into each item in the budget and so on. Buying an existing house, even if it were a fixer upper, seems like it would remove at least some of those variables. Not a recommendation to do that, just pointing it out.
..sounds like something my wife would be all into Haha