Wordpress site totalKidcare.com quickly transferred from one server to another

General information for the website: It is a social media site that connects parents with childcare providers
Description of every page/module: Website is 581MB. I'm prepared to pay more than the £20 for people who are very good at their job and quick. The end result is the most important to me so I need people who are really capable of doing this and 100% know what they are doing.
Description of requirements/features: It is quite a complex wordpress site that I need transferring from one server to another. It probably has about 60 pages now. I want someone who knows what they are doing, can start work pretty fast without saying to me maybe tomorrow or maybe next week sometime. It is very important that there is as little downtime as possible as I would lose people every hour from registering.
Specific technologies required: wordpress
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