How early do you sign a lease

[Sam LLoyd]

In my market, I usually get  notice 40-60 days before the end of the tenant's last month.  I put the property up for rent as soon as I can, find a tenant in 2-3 weeks, sign a lease about 3 weeks before they move in.  Usually zero vacancy, sometimes a week or two.  Only rarely do I have a whole month with the place sitting empty because I'm waiting for someone to filter through my screening process.  Even when that happens, when I do sign a lease, they move in 1-3 weeks after we sign.

Here is my question:  What's the longest period of time you are comfortable with between when you sign a lease and when they move in if the unit is vacant.  Specifically, it's the beginning of September right now.  I have a potential tenant that wants to move in at the end of October.  I appreciate that they are thinking ahead, and are going to give their landlord propper notice, but if I sing a lease with them this week... I will be committing to 7 more weeks of vacancy.  If I tell them I can't sign because I will probably find a tenant that wants to move in on the 1st, I could loose a good tenant... and if I don't find someone for the 1st...

I need to identify a break point for me such as "We don't sign leases more than 4 weeks before the move in date"  I'm looking for some input to help me identify that point.