Define your requirements: Before you start looking for vacant premises, it's important to define your specific requirements. Consider factors such as location, size, layout, and amenities. This will help you narrow down your search and find the right property for your business.

Research different areas: Helsinki is a large city, so it's important to research different areas to find the one that best suits your business. Consider factors such as proximity to public transportation, parking availability, and local amenities.

Contact a commercial real estate agent: A commercial real estate agent will have access to a wide range of properties and can help you find the best one to suit your needs. They can also provide advice on legal and financial matters, as well as help you negotiate the terms of a lease or purchase.

Use online resources: There are many online resources available for finding vacant premises in Helsinki. Websites such as Oikotie, Kauppalehti Toimitilat , and mlrealestate.fi are a great place to start.

Check for zoning restrictions: Before making a decision on a property, be sure to check for any zoning restrictions that may affect your business.

Inspect the property: Once you have found a property that meets your requirements, it's important to inspect it in person to ensure it is suitable for your business. 

Negotiate the terms: Once you have found a property that meets your requirements, it's important to negotiate the terms of a lease with the landlord.

Consult with legal and financial experts: before signing any documents, make sure to consult with legal and financial experts to ensure that the deal is financially sound and legally binding.