As any person with allergies will tell you, pet dander is no joke, but what will happen if you are in the market to buy a home and you are unaware that there was an animal living there before? You might not be aware of it when touring the home, there will be so many different things vying for your attention, but once you move in, itchy eyes, sneezing and other issues might make the fact obvious.
The problem is that pet dander can make it into all areas of your home and create issues for a long time. To alleviate the situation, thorough cleaning is the only remedy.
You should make sure that you have a vacuum cleaner with a HEPA filter since this will prevent the dander from being reintroduced into the air.
Talking about filters, it will help if you replace any filters you have in your HVAC system since these can hold on to pet hair and dander for a long time.