Are old VW engines reliable, well that depends. Are they easy to fix, well that depends too. I owned a '71 camper back in the mid '70’s. Even relatively new it was very slow. I also had a '74 Bus that my kids used in high school and my daughter took to college. My son had a “Squareback” for while in high school too.
The good thing about those old VW’s is that no matter how badly timed and neglected they would run. Not well, but they’d run. Keeping them going is a job for a “tinkerer” person. They need oil changes every 3,000. Valves need to be adjusted every 3 to 5,000 miles. They use an old points and condensor ignition meaning a tune up every 10,000 miles. Lot’s more regular maintenance than we are used to in today’s era of automobiles.
The good news is they are simple. If you kill the motor you can rebuild it with parts available from JC Whitney. Yet, the motor is hard to work on when installed in the bus. You have to crawl under the car and getting in from the back door takes a contortionist. Any big job means the engine comes out, which is relatively easy on a VW. The motor will leak oil not matter what you do to it.
The body is simple, the seats are simple, the heating system is complicated and likely rusted out anyway so don’t expect any heat. If you try for heat you may draw exhaust fumes into the car as the heater boxes on the motor are always rusted out.
If someone thinks they can get $7,000 for a camper bus is must be in very good shape. If you are mechanically inclined it may be fun to have a camper. If you have to pay for all your repairs I’d pass. Most mechanics that worked on these engines are retired now. You may want to find out if local mechanics are interested on working on an old bus like this one.