At some point, you have to choose to file for eviction in court. Some tenants will not budge any other way. When we file, we always call the tenant and explain that this is not an act of war and they can always stop the thing by simply paying what they owe. (In fact, it is the only remedy a landlord has.)
Once you have filed, you can still negotiate a peaceful settlement and you can do it with the eviction clock ticking.

We have negotiated monthly payments on the old balance. We have taken additional collateral or accepted a cosignor to strengthen our position. We have rented moving trucks for people and given them a crew to help them move out. We have torn three $100 bills in half; given one half to the deadbeat tenant and promised the other half if they agree to move out peacefully. See...what you are trying to do is keep the cash flowing. And if they are not paying, the cash is not flowing.

The King