What you must verify first is the core condition and integrity of the frame, hull, keel, rudder, deck - Only a really good surveyor, specialized in heavy cruising sailboats, can tell you if it worth any restoration. Forget the stories of the broker/seller.
Alden is well known builder (that does not exist unfortunately), but you need to know what is the present real core condition and why the owner abandoned the refit at such an early stage.
The engine, electronics and thruhull/seacoks fittings are your least to worry about items, as these have a more or less known cost and the installation can be more predictable around $40-50K in total. The problem is with all the unknown missing, broken etc. items, systems, tankage, rigging, sails, plumbing, fittings and here you can easily run to an expense of $150K (or more) plus years of your time and other service providers. So do your math.
A boat is way more complicated than a house and the reliability of a refit must be in a magnitude of at least 5X of anything professionally done on a house, RV etc... The less you know about boats and their professional refitting, the longer it will take and the higher the costs will be.
So this is where you may want to start... Best of luck!