I am planning to get a HP LaserJet 1020.

Based on the Specifications given in HP's website, its able to print up to 5000 pages.

On the average, how many pages can a toner print?

I am talking about normal A4 sized documents with minimal graphics.

Well, it is actually not 5000 pages for a toner.....It is 5000 pages per month duty cycle for the prnter.
As for the toner, it is around 2000 pages per toner from the hp website.

I own this printer. Now the toner almost empty. (Used for more than 1 year). I think I have printed more than 2000 pages.

remember .. the toner cartridge life of 2000 pages is based on 5% coverage

Mind elaborating on that 5% part?

5% coverage means if you add up all the black area you print on your A4 paper, it will take up 5% of A4 size.

I think it's a waste of time looking at how many pages a toner cartridge can print. Most of the time this is quite standard already. For eg, some toner can print up to 5000 pages but that's because it's bigger and it cost more. Printer market is so competitive now that nobody is so much better than other.

So, if cost is such a big issue for you then just get a low end printer of any brand will do. I personally would go for HP (for it's BRAND reliability) and OKI (for it's new lifetime warranty LED printer).

In my personal experience, it can print more than 2000 pages, with most of the pages in double spacing and full page of text.

i'm interest on HP LaserJet 1020 too, is this printer good?

Not really a cost issue here.Just trying to compare thats all.Been hearing alot of different stories from different people.