Moving database from one to another

Hi, I'm very short on time and need some help to move data from one database to another. I have a property script and a programmer has added some new features to it and has done his work on a development website. I have client who has the old script running on a different website and this client wants to have the new website. So, I will set him up with a new database but as there are new fields it will be a little harder to move the data across. I need someone to help me with this. There are 16 properties on the old site and you will have to manaully (from the clients admin area) add in the prices and a couple of extra fields because we have changed some things around... but you may be able to do these via a script, don't know.