The following are some suggestions to help guide you through the sometimes murky waters of a commercial lease negotiation:
1. Don't "Save it for the Lease"
An Offer to Lease should be reviewed by your solicitor and negotiated prior to signing, as it will either govern what is and is not included in the lease, or govern the landlord/tenant relationship if a final form lease is not completed. All issues particularly important to the tenant should be addressed in the Offer. Otherwise, the Landlord may refuse to negotiate later, taking the position that "If it was so important, it should have been raised at the Offer stage."
2. "As is, where is" may not be good enough
Often a tenant is asked to accept premises in "as is, where is" condition, or "as is, where is, subject to the completion of Landlord's Work." There is nothing wrong with agreeing to such a clause, so long as the tenant is adequately informed as to the state of that condition, and the landlord is adequately obligated to complete such Work. Accordingly, it is critical that a tenant negotiate for a full inspection right, to require that landlord satisfactorily completes the Landlord's Work at a given time, and to set out a suitable time frame within which tenant may report deficiencies for landlord to make good.
3. Restoration - avoid the exit tax
A significant and avoidable cost is often incurred by tenants at the expiration of a lease term. Tenants should negotiate for the option to remove leasehold improvements at the end of the term, but should avoid an obligation to so remove. If the landlord insists on a restoration clause wherein the tenant agrees to remove leasehold improvements at the end of the term, tenants should, at the very least, ensure that they are only required to remove those leasehold improvements installed by the tenant, and that tenant is not required to return the premises in "base building" condition. Otherwise, you may have to remove all improvements installed by the landlord and every tenant who preceded you, which would be a timely and costly endeavour.
I hope these tips will provide some guidance on the initial stages of a lease negotiation, and how best to protect your rights when taking possession of the premises and when giving them back.