[Linda Buquet]

Actually in VERY rare cases, especially if a merchant provides you with a special tool (over and above regular banners) they may say you can't have other competing merchants on the same page where you use their tool. So you always need to read the merchant's rules but again above is very rare.

If you search Google for luggage for example, you'll find lots of affiliate sites that feature Irvs Luggage, Ebags and Luggage Online all on the same site. Even though they all sell the same brands - some feel it helps the consumer shop and compare and hopefully whatever choice they make you get the commission. Some affiliates of course prefer to only show one merchant or brand. But it's totally fine to have more than one usually.