You're considered ready to exchange contracts with your
commercial property landlord once the following matters have been
concluded:

Your surveyor or solicitor has made all of the necessary
checks and has carried out a satisfactory inspection of the
building you're leasing.

Both the tenant and the landlord are completely happy with
the contracts planned out and the searches.

Any additional or conditional planning permission has been
granted.

All necessary money has been raised in order to complete the
transaction.

Until the contracts have actually been exchanged, the vendor
still has the option to let to another interested party unless
you've entered into a lockout agreement.

Lockout agreement: An agreement between a property seller
and buyer (or landlord and leaser) granting the buyer exclusive
rights to the property for a certain period of time. 
Essentially, it guarantees that you will have a contract at a later
time.

It's worth noting that lockout agreements don't apply in
Scotland.  North of the border, either party can walk away
from the deal without any form of financial penalty.

Completion of the deal will usually be one month after the
initial Exchange of Contracts, though the date can be varied prior
to the exchange - this should be clearly stated in your Heads of
Terms.

The contract is classed as completed when the balance is paid
and the keys have been passed over.  The property is now yours
either permanently or for the duration of the lease.

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