I agree with Chas. Also, I would throw in, if the unit has R-12 and still has a charge, that it would be better to have whatever is broken, fixed within reason.
The reason I say this is that a fair day with R-12 still beats a great day using R-134a.
Computers manufactured by companies such as IBM, Compaq and millions of others are by far the most popular with about 70 million machines in use worldwide. Macintosh fans note that cockroaches are far more numerous than humans and that numbers alone do not denote a higher life form. -NY Times 11/91