Wireless Repeater/Bridge

[paperwastage]

My friends and I are moving to apartments next year. We would like to share one (fast, maybe business-class, since we might be hosting our websites/content) internet connection between the three apartments that we have...

Two apartments are next to each other (ground floor, one wall separating them)

The third apartment is less than 100 feet from the other apartment in another building(also ground floor)... probably 4-5 walls between the apartments... (the apartments face the same direction, so there are multiple walls and apartment inbetween the thiird and the 1+2 apartments)

for the first two apartments next to each other, any simple router would definitely do the trick...

for the third apartment, we would like to be able to connect several ethernet-only and wifi-enabled devices together (xbox 1, a desktop, a few laptops)...

whats is the best way to get about this?... wireless bridge using dd-wrt seems nice, but is 100 feet plus walls a little too far away to get a good signal? currently i have a (crappy) $12 Netgear b/g router, but don't mind spending < $150 on 2 nice routers

also not sure if 802.11n is worth it for the bridge... 2.4ghz in probably going to be crowded, but 5ghz doesn't penetrate walls as good... laptops a mix of b/g/n