Create LOGIN [VendorAccess] WITH PASSWORD='NotTheRealPassword'

USE [WHATEVER]
Create USER [VendorAccess] FOR LOGIN [VendorAccess] 
CREATE ROLE [AlmostOwners] 
EXEC sp_addrolemember N'db_ddladmin',   N'AlmostOwners'
EXEC sp_addrolemember N'db_datareader', N'AlmostOwners'
EXEC sp_addrolemember N'db_datawriter', N'AlmostOwners'
--can the users EXECUTE procedures? comment out if false
GRANT EXECUTE TO [AlmostOwners]
--allow the users to see view proc and function definitions
Grant View Definition ON SCHEMA::[dbo] To [AlmostOwners]

--finally add our user to the role:
EXEC sp_addrolemember N'AlmostOwners',   N'VendorAccess'

DENY VIEW ANY DATABASE TO [TheNewLogin];

USE [DatabaseName];