Oh come on op, all this time and money spent? And you're not going to do anything about it?!
Nooooo....absolutely not! Op, dont let this one go because of your confidence, grab life by the horns!
Give your number to friend to casually give to him, if you dont want friends involved, sod that - go over. Dont think about it, out your front door, straight over to him (who cares about his colleagues?!) And say "hi. I need to borrow you for a quick word" and take him to one side.
Whats the worse that can happen?
Once he's with you, a nice, simple.
"Hi, im Marmalade, ive noticed you a few times across the road. If you want to go for a drink sometimes, this is me."
And press a piece of paper with your number into his hand.
Turn heels and walk back into your house and hide for the next 24 hours
Congratulate yourself for taking initiative and being brave. Have a cup of tea and do something for you and put it to the back of your mind.
Absolutely do not leave this now you've put yourself through all this.
And leave the physics alone. You weren't looking for answers, you were looking for someone to tell you, that you didn't have to do anything to get the guy.
This isn't about anything other than your own confidence.
Oh and BTW, they know nothing of his personality. He might be a complete arsehole, but he almost might be the next big thing.
And I'll tell you what, only you can find that out, nobody else can tell you that.
(Ps. Also remember that most working men won't approach a single lady living across the road, as its just not the acceptable thing to do. They could get in trouble with work, the husband, be accused of harassment, loose thier job, any number of things. Do not expect the work man from across the road to make the first move)