The redemption period only applies to the foreclosed-upon property owner. You are free to approach any other property owner about any other purchase at any other time. As a practical matter, since it is likely the case that you would *not* want to buy the other land unless the lot you purchased at foreclosure remains yours (i.e. is not redeemed), you would probably want to either not sign contracts until the end of the redemption period or else write a contigency into any contracts allowing you out if the foreclosed lot is redeemed; however, that's just to protect yourself. Unless the other land owners' property was in some way entangled with the foreclosure and involved in it--and it's not clear how that could be the case--you may approach them.