Generally the fastest and easiest way to end a tendency is to sign Form N11. It is a mutual agreement between landlord and tenant and can have any desirable date for termination. This means it can also be used to break a fixed term lease, given both parties agree.
It is OK to negotiate and offer an incentive to the tenant but the tenant cannot be forced to signing the agreement. If they are able to prove that you forced them into signing, the agreement may be rendered void. You do not necessarily have to use form N11, any written agreement will do, as long as you include the following: Names of landlord(s) and tenant(s), address of the unit, tenancy end date, signature of landlord and all tenants.
The form is commonly used when there is a breakdown in the landlord and tenant relationship or for any other reason where ending the tenancy benefits both parties. Please be aware that you cannot sign the form upon signing a lease, e.g. using this type of an agreement as a condition of a lease. This would render the agreement void. Also the agreement becomes void 30 days after the termination date, if the tenant has not moved out and the landlord has not filed with the LTB. Whenever a tenant changes their mind after signing an N11 and refuses to move out, you need to file for eviction using form L3 within 30 days of the termination date.
Find more details on forms N11 and L3 here: https://landlordselfhelp.com