Why you want to hire a professional. You can find lot of required information here plus you can get valuable experience and advise from members who has gone through these phase.
If you hire professional you will be shelling out big buck and if you take DIY route will help you in saving good buck which you can you can use it for your hifi equipment. This forum is loaded with full of information just search. If you have a specific question you can always take an advise from our fellow members.
Regards,
Santosh