I have the following problem and I need to know if there´s a way to fix it.
I have a client who was cheap enough to decline buying a backup plan for his postgreSQL d
If you have the whole data folder, you have everything you need (as long as architecture is the same). Just try restoring it on another machine before wiping this one out, in case you didn't copy something.
Just save the data directory to disk. When launching Postgres, set the parameter telling it where the data directory is (see: wiki.postgresql.org). Or remove original data directory of the fresh installation and place the copy in its place.