The budget number is a big one. Find a good boat surveyor in your area. This will be invaluble to your search. I bought a ketch rig boat six months ago with the logic that a split sail plan is easier to handle for my girlfriend, especially single-handed. A solid engine with a good service record and low hours is a no-brainer. Look for well maintained running rigging, this will let you know how often the boat was sailed and how serious the previous owner was about maintenance. Check bilge pumps and electrical systems, review every through-hull on the boat. Then have your surveyor, someone you've interviewed and established a level of trust in do it again. Sails in good condition build by a local sailmaker of good repute also speak highly of the previous owner's intentions.
When you find the boat you want, it will completely encompass your desire, beyond any recourse of logic or sanity. Be cautious, as looks may be decieving. Be prepared to spend 30-50% of the purchase price of the boat to make her absolutely sea-worthy and safe. Have her hauled and examined by your surveyor and do every repair below the waterline that he or she mentions might be advisable and coat the bottom with more than one coat of anti-fouling.
Best of luck in your search,
Sailing a '74 Challenger 40' Ketch rig out of San Francisco