Memory Foam Carrying

Are divorce contracts valid if they aren’t written by lawyers? What about hand written contracts?
Before I moved out of my wifes apartment I talked her into signing over a box spring and $700 memory foam mattress to me for $20 because she was hungry for a cheeseburger. It was hand written.
She doesn’t think things through very thoroughly and just compulsively does stuff like this. If I can get her to sign a retro-active prenup for $100 or something like that, and print it up on my computer, what are the odds it would carry any weight in court?
And what about the hand written contract that I get the mattress? Would it carry any legal weight?
any written document written down and signed can be used in court. However, it is up to a judge if permits it or not! So you can try and don;t forget she has the right to fight that paper that it was signed under duress etc..
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