C:\Windows\system32>net start mssqlserver /f /m /t3608

The SQL Server (MSSQLSERVER) service is starting..

The SQL Server (MSSQLSERVER) service was started successfully.

Firstly don't start sql server as a service, also -f implies -m, you just need the following command from the Windows command prompt

SQLSERVR.EXE –f –T 3608

If you have backups of the 3 dataabses, restore them to another similar instance as user databases. So restore them as

Usermaster

Usermodel

Usermsdb

Detach them from the instance and rename the disk files back, then plug them back into the original instance.