Pineapple Guava is my favorite...
Grows fast, year round interest too.

Sounds like you have neighbors to keep out?? Also, do you want to screen them? A nice 8' high hedge, low maintenance with lots of color would be the Mutabilis rose. Very healthy, and no spraying needed. A fast growing, 20 x 20' (eventually) evergreen one would be Russian olive, which would give fall fragrance. If you need high and fast, awabuki viburnum grows about 30 feet high, and is also evergreen. It flowers in old age, but takes a long time to do so in my experience.

Well, we the road runs parallel with the house and those lovely folks behind us think our front yard is the perfect spot for spinning donuts, etc. We are going to put up a low fence, but we want something for privacy too.

Thanks!