Do I buy the new Business and Hobbies EP or wait?

I mean, is it something that interests you in terms of gameplay?

Of course! I just don’t know if it’s worth paying full price right now 

Then wait for a sale. Usually if I have to question it I'll usually wait. Not usually for a sale, but if I'll use it as much as I think I will. Most packs I usually know I want off the jump and buy it right at pre-order. Don't even matter for price usually as I got a pack for free (My First Pet Stuff) and STILL don't use it and just wish I never bothered with it.

This pack here I see a lot of opportunities for Sims to be able to have different businesses to visit. Been wanting for a long time for sims to be able to pay fees on lots like Museums and such or even having a Gym fee. That alone already got me interested along with sims being able to do shady stuff.

Consider looking at some Game Changers to see if you REALLY want it. Oshinsims, DrGluon and James Turner really sold it to me seeing all the things you can do. Daycares, Movie theaters and even having one that functions like a motel/hotel.

I think it's worth it, personally, but I have a lot of other packs.  The bonus items will be available for a month, so take a day this weekend or a few evenings and watch someone's Early access Let's Play on YouTube (if possible, a Sims YouTuber that plays similar to the way you do) and see if you like what you see.

There's a thread that lists a bunch of early access videos, so I'd start there to see who you want to watch.

Check out simgirl's early access thread that have a variety of videos showing gameplay.

Businesses And Hobbies Early Access Videos | EA Forums - 11938455

Might help you make a definite decision. 

That's a question only you can answer. The answer is different for different simmers. I personally think the pack looks very promising. It offers lots of potential through it's flexibility in choosing business activities. But if you want to know if it offers enough for you personally, it is best to watch or read a few reviews. 

personally. I don´t recommend it. I´ve been playing for 45 minutes. It´s dissapointing in cross-pack compatibility and building fredom.

Always best to wait for a sale. They really do not put enough content in expansions to warrant the full price. They keep selling game packs for the price of expansions.