No, you cannot put someone else down as a co-owner of a co-op after you move in. If they have not been included in the board application process, they are not approved by the board. In order to have the other person as a co-owner, you should include them in the application from the start. If you wanted to ammend your shares in the corporation and proprietary lease to include the other person, you would have to go through the board to do that.
Also, to ammend some misinformation below, a co-owner does not have to be on the mortgage as well. I know this for a fact through experience, where not all parties were on the mortgage. There is no obligation for that. The reverse, however, is true. If they are on the mortgage, they must then be an owner.
Halstead Property, LLC
Charlie Summers, VP Bellmarc Downtown 917-376-1648
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Keller Williams Landmark II
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When you buy a co-op, you own shares of stock in the cooperative corporation and you also have a lease to your particular apartment. Therefore, the co-op board must approve all changes in ownership of the share of the cooperative corporation. They have control over who can live in the building. This means submitting to an extensive examination by the board. If you have a mortgage, you will also need to check with your mortgage lender.
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