Tough decision. I would be very reluctant to leave a kid behind for a year and a half. If you took that option and considering that you would be in a new job, how often would you be able to visit? How would you manage college visits and all of those decisions long distance? It was an overwhelming time.
Honestly for a kid who has already had a serious injury, I would be discouraging a D3 college football path. What is the purpose of pursuing D3 sports? There are no scholarships, no where to go after, and he risks injuries with lifelong effects. If he's interested in a rigorous course of study, I would be encouraging him to leave sports behind after high school for academics and his future.
You also mention that he isn't terribly social. If most of his time outside of school and sports is at home with you all then I think being without family would be harder than you imagine.
Given all that, I would be looking for the best high school and moving him. Put your efforts to finding a school where his credits would transfer as easily as possible with the hopeful bonus of a school where he could play football.
I completely understand it being impossible for one parent to stay behind. With college costs looming, I don't think that we would choose to maintain two households.
As far as your school/job decision, I would find a job, get everyone else settled, and decide later whether to make a change.
My sister worked in Reston years ago and lived in Sterling.
Good luck and be sure to come back and let us know how it went.
In DS's case, the purpose playing D3 (other than loving the game itself) will serve is that it actually will be beneficial to him to play because he really wants to pursue college coaching as a career. He isn't blind to the fact that it is a tough gig, and will be going to school for PT, but he would like to at least give it a shot. As long as he has a backup plan, I'm not going to discourage it....so many people hate their jobs, so why tell a 16 year old kid, who has unlimited opportunity right now to pursue whatever he wants to, that a par is unobtainable? He'll figure out the path he needs to take eventually.....I'll let him keep his dream for a while longer.
He is not the party-boy type, meaning I am not afraid he will be stupid and get drunk and high every weekend if we are not there to monitor him, and he is serious about his training so between school and football he is booked pretty much all day, every day, and spends a lot of the weekend catching up on homework so he it often tired and not wanting to go out and party till 3am. None of that means he is anti-social or shy. He is very outgoing and charismatic - he has no trouble speaking up for himself, making phone calls, or talking to people. He spends *enough* time with friends....and you have to remember that he spends upwards of 25 hours a week with 60 other boys his age outside of school hours, so by the time he gets home, he has had enough of teenagers! He has just started driving, so he wasn't really dating yet, but he did just ask a girl out to the movies right before Christmas break. So I think he's fine socially.
I realize that but if he's already had an injury that kept him out for so long and he's interested in a rigorous course of study, I'd focus on the best school for his future career rather than a D3 school to continue football. College level sports a hugely time consuming. I personally know several young people who realized that since they had no future in sports it was time to give it up and focus on academics.
If he already has a first choice school, then I would make decisions based on making that school a reality.
DS plays to play, not to play for other people. He has always said that he would be perfectly fine to play with nobody in the stands watching because he is focused on what he is doing, not the glory. As a lineman, there really isn't a lot of glory outside of getting a sack or a big tackle at a key moment. He plays to play, because it is a part of him. He missed it desperately when he was out and worked very hard to get back. He missed his sophomore season, and came back to play the last 5 games of his Junior year. There are high expectations on his shoulders (LOL, literally and figuratively!) for his senior year. Not from DH and I, but from his coaching staff and the local/conference world.
He has said, however, if he gets injured again, he will not play. He also will not play if he doesn't get recruited with an offer of an (academic) scholarship to play at a D3 school - he would go to his #1 school then instead. He is a realist and as much as he would love to live every boys dream of playing a sport the rest of his life, he knows it's not reality. He's not even thinking about D1 or even D2 colleges (as a player, I mean. As a student, his first choice is a D1 school) - he just wants to get some college experience as a player so he can have the experience and exposure to open doors for coaching. If that doesn't work out...he goes to first choice school and becomes a physical therapist.