I guess I`m a newbie as I haven't played for a while.
As of just started to get the hang of things so I am asking What do I need to look out for when buying new pets. also I cant decide on what breed to be my main focus. Looking for a rarish type pet.

Buying pets is generally for personal happiness rather than monetary gain. Money usually flows through items rather than pets. While there are pets that cost more than others, the ones that do usually cost more to obtain, so it balances out in the end.

But I guess if you want to know how rarity goes. The most rare are themed fabled pets. Fabled pets are those found not through battling/exploring in non-festival zones. They are: nephini, puffadore, aeridini, griffi, ryori, ny'vene. Out of those, nephinis are generally the most expensive, and ny'venes the least.

"Themed pets" is synonymous with "Tagged pets." These pets are obtainable only during a seasonal festival. There are 4 main festivals throughout the year, like the seasons fall, winter, spring, summer. There are also smaller festivals such as valentines for example. During these festivals, there will be a special zone that you can explore to find themed pets.

Here is an example of one:


You'll notice in the genetics section it says in purple, "Chocolate Cherry Puffadore."



Tagged pets will have some name for whatever there theme is there. You can search for themed pets using the advanced search. Note: Not all themes are equal in pricing. The less pets that were released of a given theme, the more it's worth (generally). One of the more populated fabled themed is the "Spotted Woodpecker Aeridini" which there are over 650 of. Versus for say the "Chilly Paws Puffadore" there are less than 60 of these in existence.

In terms of other pets, honestly just buy what you like. :)