Got on GovX today after looking at a resort in Cancun and it was 1/2 the price as Cheapcarribean and says all inclusive. Cheap Caribbean says Ultimate luxury Inclusive. Trying to figure out if there are big difference and if the difference in costs are worth it or the GovX deal is good to go. For two families with kids one of $9080 and GovX was $4500

It all depends on the resort.  You didn’t list the resort you were looking at.  
Don’t get suckered in to vacation packages based on price alone. Reputable travel agencies are all pretty comparable so if you’re seeing half the price with one over the other, there’s something askew or there are conditions not being listed.

That’s kind of what I was thinking. Looking at the Now Sapphire Riviera Maya.

Heard of them.  I don't trust them.

Went to the Now Jade Riviera Cancun for my honeymoon back in 2010 and had a blast. Food could have been better, but it wasn’t bad. Worst part was how far from everything else we were. Long shuttle rides for the excursions we did. Didn’t know when we went the top shelf booze was included too. Spent the first day or so drinking barely cold Dos Equis on tap, later learned they had Coors Light in cans in the fridge, and well hard alcohol.