Why do you only want to go to 4.7.4 versus 4.8.1.SP1?
We can give you a quote but need more info about any customizations you might have, 3rd party addons, etc.
Click the link in my signature and will be happy to work with you.
Because my license only allows Multivendor upgrades till 26th June, when version 4.7.4 was current.