UO8s make nice beater bikes and excellent urban fixies. Keep the headset and bottom bracket maintained, as they can be difficult to replace.
Check your rims; if they are steel, consider replacing them for daily riding (alloy rims brake better than steel). It likely has a cottered crank, and I recommend trying to replace these with cotterless eventually. Take your time; replacement parts can be found cheaply in thrifts and the like if you're patient.
Pricing seems to vary. I bought mine for five dollars and fixed it up as a fixed gear with old parts from my basement; the total investment was just under 40$. I personally wouldn't pay more than 25$ for one, but I've seen them go for more on ebay and one poster here swears 125-250$ is fair for one modernized and in good condition.
The bikes do have some odd issues-- weird seatpost sizing, 96mm front dropout width, but all this can be overcome with a tad of ingenuity. There's a reason why people still like riding them.
__________________
"It's always darkest right before it goes completely black"
Waste your money!
Buy my comic book!