What percentage of the 5 miles do you think are hills? Also, how steep of a hill? If it's not that steep, a regular hub motor will probably work. If it's a pretty steep hill and you don't want to pedal, you should look at the 5305 crystalyte hub motor, also called the Phoenix Brute. It will power you up any hill without pedaling.

There's also some other hub motors that are powerful and will power you up hills. I think the Ezee would work. The 2806 Nine Continent might work. The advantage that the Ezee has over the 5305 is that the Ezee needs less battery but the Ezee also is a little slower and probably a little less powerful than the 5305. The 5303 is a very big motor but very powerful and very reliable.

If it's not much hill or not a big hill, you can look at the Aotema kit from hightekbikes.com for about $300 total (with everything exept batteries). Or you can look at the kits from http://e-bikekit.com . Those two websites are well known in the EV community and have an established record of being trustworthy. Another well known website is http://ebikes.ca . It's based out of canada. That's where I bought my e-bike kit. It was 5303 hub motor with controller.

For batteries, I don't recommend anything lower than about 15 AH for SLA batteries and 10 AH for lifepo4. So something like 36v15 AH in SLA or 36v 10AH in lifepo4 would be okay.