The 235 is easily one of the best 22-25 footers every made.
the site is
http://beneteau235.com/
LOTS of great info, to read the forums you have to join.
The standard location of the battery is aft of the head under the sliding chart table. A common mod is to move it under the port settee, this also helps P/S boat balance.
Thing to look for? The boats are generally very well made with over-speced hardware. the hull is solid and the decks almost never get wet as beneteau normally only drills in solid areas.
Transom/hull joint. A weak spot of the design. Look over the outer flange.
Mast. The Z190 spar is light for the boat and the early ones often broke at the spreaders. A 90 should have the upgraded spreader kit.
Keel is iron, check for condition, along with bolts (they are NOT nuts as typical)
The headliner, if still up, WILL fall. Just a matter of time. Fixing is a labor intensive job. Trust me.