Before we start keep in mind that only users with Office Administrator / Organisation Manager access can create and remove contact types tags.
Once logged into Base, click on the cogwheel top right of the screen
Then select Settings
Select Office on the next screen
Select more and choose to Customize
A new screen will open, select Contacts.
Click on the edit button:
On the tag field, type in the description you wish to add, which should typically be a role e.g.
then click close to exit, and press save.
To remove a contact type just press on the trash icon next to the type
When you now open a contact you will be able to tag them as one of your contact types, e.g. seller. You can select multiple types per contact, e.g. a contact could be a buyer and seller.
You can also create personal tags for contacts (e.g. cash buyer, pre-qualified), more info here.