Once a landlord and a prospective tenant have agreed to terms, the landlord will draft a lease a send it to the tenant to review, make changes (to the legal terms, not business points), and execute. This process can be immediate or can take months depending on the simplicity of the deal and how quickly the landlord, tenant, and their attorneys act.
On a straightforward deal for a relatively small space, the landlord will expect the tenant to sign the leases within a week or two. The landlord will be more patient if the tenant is actively asking questions or making changes to the lease than if they are unresponsive for a week and a half.
Typically, when a landlord will only send one tenant a lease at a time and will not entertain other offers while they are waiting for the signature. However, if the tenant is unresponsive or attempting to renegotiate the business terms, the landlord may revert to back up offers or encourage other tenants to look at the space.
If you are looking for space and your desired space has a lease out for signature, you are basically on hold. Sometimes tenants or landlords have a change of heart and it doesn’t work out, but it’s hard to predict how long it will take to know. The tenant with the lease can walk away from the deal the next day or drag it out for another three weeks then sign.
The best way to approach the landlord if you want a space that has a lease out is to send a strong offer to the owner and tell ownership that you are ready to move forward asap if there is a snag in the negotiations with the tenant with the lease. I would also send them reminders that you are still interested about once a week. This serves a couple functions: