If you're good at network stuff, then you know about
the map. You're basically looking at 65yds from the node, and is a piece of cake for any up to date router out there. Sure they may get one bar, but they're just browsing you say.
I've got two wireless routers; one old and one new. Both reach down the block well in a hill-covered city environment...about 50yds as the pigskin flies. The Linksys E4200 is awesome on the outreach as I see it with one bar about a mile away. The older DIR 655 drops out, but it's still at about 100yds away before doing so. I can still cruise the interwebs just fine with it, but don't download 50MB files and expect perfection. I wouldn't add a repeater or bridge at this point. Depending on what you have (tell us please), you may get off with a better $75 wireless router to do it all.
On the camera side, you can get complicated or dumb it down IMO. I have a K-Guard set from Newegg ($300) with an unused drive and wired it into a
D-link DGS 1100-16. Wiring the house is a must IMO, and adding these to it was easy. To go wireless with the cams is hard and expensive IMO. At 450Ft, you run right back into the wall of the prior discussion but with more demands on bandwidth priority. A good basic wireless camera can cost you more than trenching a hardwire over to the stable and a great LAN camera. And that's a camera that you can manipulate via the web or a smartphone app. I use to love it when folks would give me the ability to move their cameras around...and that's possible here.