Unfortunately, roadsters tend to be pricier than MTBs, or hybrids. Good buys can be had in the used market, but one must know what one is doing.
I just sold a very nice Giant roadster for 300.00. It was almost 20 years old, but in excellent shape.
If such a bike needed only a few repairs and you had to have the work done at a shop, you could easily double your money and it would be no bargain at all.