I am thinking of buying a condo in Pattaya. 

  I already have a yellow book and pink id card for my present residence. So it is my understanding can only has the yellow book and pink card for one residence.

  With this in mind if I go from my present home to the condo for a week is it necessary to tell immigration ?  Does not  make sense to do .sense both places are my residence. 

8 minutes ago, lovelomsak said:

With this in mind if I go from my present home to the condo for a week is it necessary to tell immigration ? 

Technically yes according to the rules.

But in reality no since they cannot enforce something they do not know about.