Until a written contract is signed by BOTH PARTIES (buyer & seller)), you are free to do what you please, at your own risk (of lossing the deal)

If the offer has been accepted - I assume there are signatures to that effect. However, when you say co-buyer, again I assume you mean you will be on the loan ap.

I believe both signatures would be required at the loan table, but if the contract only has the one buyer listed - that one buyer is obligated as long as there are no contingencies. You will have to clarify for a better answer, but at face value it seems as though your "co-buyer" just bought a house with or without you.

Are you working with a Realtor on this transaction? Is this new or existing construction? If I were the seller, while I would entertain all offers, I would be wary about entertianing an offer the second time around.

We could use a little more information here. Also, did you both sign the offer to purchase? Did the sellers accept your offer? Are you thinking you could have purchased it for less? Hummm.

Kolozsvary,
To help you out, we need more information. Did you already sign the offer at $305K? Or only your co-buyer signed? Is your concern that your first offer was accepted? If so, we've got a whole thread on that issue... Please re-post these answers, and we'll try to help...