Cost of Living in Guangzhou

I read 26k usd is enough to live, so getting 70-90k usd is very very good, correct?

to Patrick: It varies a lot family to family.

You can survive with 60k RMB or you want to live like a middle class Chinese, then somewhere around 130K RMB.
But usually a foreigner knows little about where to shop and bargain and probably travel more often than local Chinese I would say 180K RMB is needed to live comfortable. So it's about USD $26000. But you won't be able to save a lot.

Asadar, please add those links under Sources and References. Also, you can email us directly at contact@numbeo.com

Now, the rent.
If you want to stay in the complex with 24|7 security, underground parking, swimming pool, videophones, own infrastructure, that's fine, but, again. than you need to compare it with similar class in EU and|or US and it will be either premium or elite class real estate (business class, at least). Don't you thing this is a sort of the wrong comparison model?
You can find a 3-br 'flat' in traditional Chinese house for as much as 700-1000 RMB (outside of the city center, but there WILL be a subway station in like 10 minutes walking distance), the total area will be like 70 sq.m. OR you can even find a room for 300, that will be a small one(like 10-12 sq.m.), but anyway.
Or you can (and that's what we did) rent a furnished 130 sq.m. flat in the modern complex with it's own territory, guards, pool, etc for as much as 3k per month. Again, that's Huangpu, not Tianhe, but anyway. And somewhat like 400 yuan per month you will pay for the management, there is no such fee in traditional houses.

Moreover, all the other prices are irrealistic and way high. Here are some examples.
1. Rice. This is a standard food here, not "bread" or "cheese". It is easy to find the rice for 2.40-2.60 per 500g in almost ANY supermarket, not mentioning the marketplaces. That's 5 per kilo, not 10
2. EGGS. I am buying for somewhat like 3.50-4 per 500g, you need to pick up yourself and weight 'em as those which are packed (like 6-pack 10-pack, etc) are enormously expensive and no one is buying 'em (except foreigners, probably).
3. Bananas. In ALL the shops nearby I see the price 1.5-2 per 500g, so where did this 9 per kilo came from??? Is this some sort of a 'special imported bananas, much better ans sweeter?'
4. Clothes. Have you heard anything about Taobao? You can find a pair of jeans for like 30 yuan there, if you're scared about quality, you pay 60 -and that's it!
Potato is overpriced, chicken breasts are overpriced. Even bread! Go to Auchan and you can see lotsa bread in a price range 4.5-7 per 500g. So, if you know where to buy (or, actually, where NOT to buy), the real purchasing power of your salary will be at least 1.5x higher than you expect based on the digits here.