Ok, so I'm a n00b, but I've done a bit of lurking here, done some looking around, and am now ready to get some suggestions.

I *ALMOST* pulled the trigger on a Republic until I did my research. Now I see the BD love spread around, but they don't have flat bars. I'm just doing casual/errand rides, zero racing; just want something to work different muscles in my bent that I can do short trail rides on.

Musts:
flip-slop
Flat bar
front brake
~300 bucks - I can go as high as 400, but prefer not to.

would like:
decent wheels I don't have to true every ride.
frame color choice.

DO NOT WANT:
track geometry. Relaxed is good. Don't harsh my mellow, man.

I'd love some suggestions on models. BD bike and buy a flat bar? If so, what other parts must I swap?

Buy a flat bar.

Well the only SS on BD I see that is not a track frame is Motobecane Fantom Cross UNO. I guess you can do that and get flat bars. I think it's good if it's just going to be a commute/errand bike since it's steel and has the wider tires. But it's $400

eliminating track geometry seems to leave you with that or converting an old road bike.

step 1) buy a bike from BD
step 2) buy a flat bar at lbs/co-op
step 3) install said bar on bike.

This

and

wat

if I get a flat bar do I need to change out the stem as well?

Not if you get a flat bar that's the same size.