I am not a lawyer, but have an interest in following real estate laws. What Lyle Gant has stated is partially true. An outright sale cannot take place without the sign off of all owners.
When one owner wants to sell and other owner(s) do not, there is a "thing" called a partition action. One owner can indeed force a sale.
I have included a link here that is merely to help understand the applicable law. It is not an endorsement of this site.
Beware of the cheap lawyer. Even the qualified lawyer. A lawyer who runs up billable hours on these type of actions can file a lien against your portion of the real estate proceeds, so he/she will get paid. Plus, your relative is going to have legal expenses, which may get charged against the estate.
I just can't tell you how fast a legal process a partition action is in this state or in your county. (i.e. Florida foreclosures can take years.)
Your better plan may be to save the legal expenses, work together to get the best price for the sale of the property, agree on the timing, and figure out where you are going to live next.
Best wishes.
Partition Action Florida: Real Estate Law Statute & Lawsuit