RunTime Options

Once you open Start-Sql.ps1 in PowerShell ISE. There are a myriad of options you can configure, but only a few you must

The $ht object is a hashtable, it is a simply key/value pair collection that is pass directly into the Install Process.

The values for DataCenter, SqlVersion and SqlEdition will be validated against what you have setup in the respective sections of the Config File Setup, thus ensure those are valid against your Config.
#Required Parameters
$ht.Add("DataCenter", 'Data Center 1')
$ht.Add("SqlVersion", 'Sql2012') 
$ht.Add("SqlEdition", 'Developer') 

The only other REQUIRED parameter is the SA password, which unfortunately is pass in plain text.
$ht.Add("SysAdminPassword", 'SQL4tw!')

Service Accounts

Service Accounts and respective passwords can be set, otherwise will default, As defined by Microsoft https://msdn.microsoft.com/en-us/library/ms143504.aspx Other account types to Come
$ht.Add("sqlServiceAccount", 'SQLFTW\SQLService')
$ht.Add("sqlServicePassword", 'SQL4tw!')
$ht.Add("isServiceAccount", 'SQLFTW\SQLService')
$ht.Add("isServicePassword", 'SQL4tw!')
$ht.Add("agtServiceAccount", 'SQLFTW\SQLService')
$ht.Add("agtServicePassword", 'SQL4tw!')
$ht.Add("ftServiceAccount", 'SQLFTW\SQLService')
$ht.Add("ftServicePassword", 'SQL4tw!')


Other optional, regularly used parameters:

Custom SQL Install Options

While your regular install options should be setup in the Version specific Configuration Template, you can override those individual features by using the $overrides hashtable in this manner:
$overrides.Add("SQLBACKUPDIR", 'C:\$Recycle.Bin')
$overrides.Add("SQLUSERDBDIR", 'H:\MSSQL10\MSSQL\Data')
$overrides.Add("SQLUSERDBLOGDIR", 'H:\MSSQL10\MSSQL\Logs')

Script Control and Output

Debug

Debug can be initiated in one of two ways:
Add the Parameter:
$ht.Add("Debug", 'True')

Or simply pass the -Debug parameter directly to the Run-Install Command
Run-Install -Parameters $ht -TemplateOverrides $overrides -Verbose -Full -Debug

Simulation

Just as debug, a simulated/whatif execution can be initiated in one of two ways:
Add the Parameter:
$ht.Add("Simulation", 'True')

Or simply pass the -WhatIf parameter directly to the Run-Install Command
Run-Install -Parameters $ht -TemplateOverrides $overrides -Verbose -Full -WhatIf