Unless this is a hobby car and you intend to do the work yourself, it is just not worth it.

Leaving aside the point that the car is over 30 years old and despite those old Volvos' reputation for anvil-like reliability it's going to have problems - it depends. Was the engine overheated? (Most common reason for head gasket blowing.) Any other engine damage? Did coolant get into the oil and damage bottom end bearings? How well has it been maintained over the decades? Are the rubber parts (seals, brake hoses, etc.) original and deteriorated?

If you can do the work yourself you can replace the head gasket for the cost of the gasket and any other ancillary parts that may be required if there is no other damage. However when you get into it there's no telling what you'll find. Cylinder head could be warped or cracked. You'll be dealing with parts and fasteners that have been together for over 30 years and will probably be reluctant to come apart, rusty fasteners are likely to break and need to be dealt with.

A head gasket job at a mechanic might well cost as much as you pay for the car, and that's if there's nothing else needed but the gasket and the job goes well. Then you could find that the transmission is on its way out.

So I'd say if you can get the car cheaper and do the work yourself maybe it might be worth a shot. But if you have to pay a mechanic you could be in for a wallet-emptying experience.

I would not buy that vehicle unless you plan to make it a project vehicle and do all the work yourself.  Realize it is 31+ years old and will need more work than just fixing a blown head gasket such as replacing rubber, plastic, belts, seals, bushings, fixing leaks, etc - all those materials will have aged/be worn and need replacing.

Let's see ... 30 year old car. Doesn't run. Needs a lot of work and money to even make it do anything.

AND the owner actually wants MONEY for it. {blackemo}:laughtertotears: