Please Help Did I buy too Big of a toy hauler?

Ok my truck is a 2005 toyota tacoma pre-runner 4.0 V6 with factory tow pkg 2WD class 4 hitch
My max tow capacity is 6,500 my max hitch weight is 650#

I put a deposit on a 2017 KZ 19FKTH toy hauler the GVWR of camper is 4000#

Dry weight is 2530# The hitch weight is 420#

My concern is that if I try to tow it with no motorcycle weight in the rear of camper The hitch weight is really up there

Dry hitch weight 420#
battery and propane 66#
fastway wd hitch hardware 80#
full 6 gal. hot water heater 48#
So im already at 614# hitch weight without loading anything into the front area of the camper right?

Is it true that anything I put inside in front of the campers axle has to be added into hitch weight?

I was also told if the bike is in the back it will reduce hitch weight by about 100# since the bike weighs 600 pounds

But we dont always want to take the bike

Also the payload of my truck is 1169 pounds

Here is the link to full specs of the toy hauler http://www.kz-rv.com/products/sportsmen-classic-travel-trailers/19FKTH.html

thanks for any info or help