I hope you get a surveyor to check out the boat, for issues besides the broken deck.
Lots of water could have gotten in there.
If that started as a Brown Searunner 25, there are a few changes. Good/ Bad?? Who knows.
The amas are not stock design, nor is the aka connection (the "bury" of the aka looks short).
I can't imagine why the rudder has a leading edge cut out so low, unless that rudder was taken from another boat. The tiller connection is strangely high, but might not matter.
Has the mast been broken or cut off in the last picture?
The picture of the transom shows a rounded hull. If so that is not original from the Searunner design - not necessarily bad if built well.
Spend money to see what the real condition is before trying to save this boat.
Good luck