It would take 2-3 weeks 24/7 botting. By charging per hour, it would be too dear. It is roughly 11,000,000 XP needed to get to 99 from 80. Another service where they run multiple VPS' with multiple bots would be more to your liking. If I were to use the Soulwars PRO bot, it would be a different story. As I am using Perfecticus Fighter, I'd be getting about 30,000 XP per hour. That's 366 hours > 15 days. As other services charge by level (as they can gain from 98 to 99 in one day using Soulwars) it would be cheaper to use their services.
If you wish to use my services and accept to the 24/7 botting for 366 hours (can be distributed) then please post back notifying me. As I do not expect you to go through with this services offer, I wish you luck in finding a cheaper alternative. =]