Hey y'all. For those of you who haven't heard, I love to play with networking devices. I am currently in the process of helping my neighbors expand their wireless coverage. I have provided a picture created with MS Paint to help you visualize my situation.
Basically, I have a gateway connected to an apple AirPort AP. The wireless signal distributed by the AP is being repeated by a- you guessed it- wireless repeater. I installed the wireless repeater the other day, and it seemed to help a lot. The red wavey lines show signal strength before the repeater. The similarly shaped black lines represent the repeated signal- (as determined by a WiFi brown townyzer.)

I haven't checked, but I know that none of the wireless signal is getting into the barn. I need the whole property to the right of the river to have reliable wireless coverage. I can only spend another $80, so I feel like most of you are going to say "get something + dd-wrt." My main concern is the barn. Right above the little -90dbm mark (which isn't too accurate) is the farthest distance away that we successfully loaded a webpage.
So guys, do you think I should get one really good repeater, two decent ones, two or three old routers with dd-wrt, or something else?