It could be a good deal. However, take it to a mechanic and have him VERIFY the mileage. This is absolutely essential on that car. The 1994 - 1998 SN95 style Mustangs used very low quality plastic gears for the odometer. It was very common for the teeth to become worn out and the odometer to stop working. I have repaired a ton of these and it is a seriously delicate job that requires removing the whole instrument cluster from the dash and doing some very careful, tricky work with the gauges and needles. 

Most guys leave it broken, then either fix it right before sale or say, "Oh it just went out" when in fact it has been out for 100k miles. I can not stress enough that you want to verify the mileage before spending your money. They are good cars, parts are cheap, and you can have a lot of fun with them. But just make sure you cover your bases and get a mechanic to check it out. If it checks out, go $3000 cash and you have a good deal.