Every year you’re exposed to a rip off & many are caught just by doing what seems right …
I’ve long been a believer in the Kaspersky range of PC protection and recommend them to anyone contemplating the purchase of a comprehensive virus/spyware/malware detection suite… 
BUT
When your initial purchase expires DON’T make the mistake of believing that, as a valued customer, you’ll be offered discounted rates for renewal.
Most Software Retailers are quite happy to rip off existing customers by charging far more for renewals than available elsewhere.
Sure I received the offer of a 30% reduction from retail when renewing my 3-PC 2-Year Anti Virus suite – but after googling ‘Kaspersky Internet Security’, I was able to buy it online retail (from a Genuine re-seller) for $53.50 LESS (And that included $16 for postage).
If you are more adventurous you can even search for your chosen software on eBay & find genuine discounts on products with un-activated licences – this is perfectly legal and can bring HUGE discounts … but be sure it is a legitimate product. (Paying via Credit Card will offer some protection against fraud – Paypal? Not so much – their track-record is poor)
I’ve heard all of the manufacturer’s bleatings about ‘we don’t set the price’ we only suggest a RRP – but I fail to see how a retailer with overheads to consider can sell at a severely discounted price to that of the source.
So Google before renewal!
But beware of rip offs
Of course the internet is rife with unscrupulous sellers all to eager to get your money & details – so don’t just head for the cheapest deal … make sure that the online store is run by a legitimate company & search for any negative consumer reports. It’s also wise to use some form of ‘payment protection’ so that you are not left without recourse if the cheaper price is a rip-off!