What is the going rate for a full site revamp to make it look modern and optimised for conversion?
It depends on the size/type/complexity of the website, literally anything from £ 30 upward
Should we use an established agency or a freelancer?
An agency will typically cost you more, as there's typically a lot more overhead, but also a lot of difference.
If you know exactly what you want, how to achieve it and really just someone to-do the technical side for you then you'll probably find with a freelancer.
If you want broader thinking, hand holiding, the ability to call upon a larger number of skillsets, some guarantees or deadlines, liability and such then you probably want an agency.
Do they need to have in-house SEO or can we take advice from our existing agency?
The new website should take into consideration your other SEO and marketing activities. So either or both, just ensure if both that they are willing/able/billing for working together.
What are the key questions we should ask to be sure the agency / freelancer knows what they are doing
Like with a plumber. Ask for examples of work. Ask for references or recommendations. Check the work and check the references.
However, we are not sure where to start in terms.
Start by arranging meetings with local designers/developers/agencies, this should cost you nothing. The more you meet, the easier it will be, be honest about not knowing where to start and if there's anything you don't understand. If something cannot be explained in a way so that you fully understand as the client, or the provider is not willing to, then you probably need to provide a different/better provider. The communication is the most difficult bit IMHO, the technology kinda takes care of itself.
Any other pointers we should know?
Unless you pay either a freelancer or agency what will seem to you like a ludicrous amount of money, then you should expect that you need to provide a large amount of time and consideration from your business to the provider, to ensure the project stays on vision and deadline. A lot of people seem to forget this as a cost.
