Me and two other friends recently signed as lease that included our names as well as another one of our friends who couldn't show up for the signing.

Now, all four of us are listed as tenants, however only us three signed the lease and, because our circumstances have changed, we can't afford the propery anymore.

Does the fact that not all of the listed tenants have signed the lease prevent it (or have any bearing at all on it) from being valid?

Nope. You will have to find another tenant to make up for the diff.

Nope. You will have to find another tenant to make up for the diff.

So even though the lease states that this is an agreement between us four and the landlord and one of the four didn't sign its still valid? That doesn't seem to make sense...