Convert ePub or Word document to Kindle Mobi

I have a 500 pg well formatted MS Word file (good use of styles throughout) that needs to be converted to the Amazon Kindle MOBI format. I also have it in EPUB format and it is looking very good there. However the conversion to a good looking, error free MOBI format is beyond my skill set. I must tell you that I am very particular and in a hurry. I had another Freelancer working on this project and he has not been very responsive. Sometimes taking 48 hours to get back to me. I need this project done quickly. I think someone very skilled at InDesign and Kindle work could probably do this in a couple of hours, someone less skilled may take days; I don't have days! So if you do not have these skills, do not apply. I've already canceled the project one time (and this Freelancer will not be getting a great review), I don't want to do it again. The MOBI file must look completely professional. Great work, gets a great review. Because most of the work is already done for you (both my PDF and EPUB are flawless) I don't expect bids over my budget.