Drue, its probably apples to oranges here, but it cost me ~20k to renovate a 1 acre pond here in CA. The cost for equipment and contractors is wildy variable across the country. it is very expensive here, and probably less in SC. I would expect a 3-acre renovation to take at least 3 weeks.
the best thing you could do is educate yerself in pond construction (through literary material available thru pondboss......and no, nobody here recieves kickbacks for plugging PB books).
after some self-education you could then manage the renovation and direct yer contractor efficiently which would save you some money over just hiring it out blind and opening yerself up to making mistakes or being overcharged. you could also hire a pond consultant if yer budget allows it.
some mistakes might include breaching the clay layer that keeps water in yer pond or not rebuilding the broken dam properly. some value added items you might get from some self-education may inlude upgrades to spillway or drain pipe performance, upgrades on hard structure for fish, re-sloped banks to inhibit weed growth.....etc....
good luck.
