Trouble with a partner

[Glenn Davis]

Hello Guys, 

So a old friend found out I was an investor in real estate and proposed a deal to go in 50/50 on a few properties. The plan was to buy an allotment of homes for long term. The money for the first home came from a bank account that both our names were on and both or our names are on the deed to the home as well. Now the partner for whatever the resin is unhappy and wants to get me to sign over the rights without spiting the value of the home. We did not have a signed contract for this deal it was done on a handshake so that's the first mistake noted .I need some help on how I can protect my investment?