Let me see if I can summarize for you.
Here's a link
to the spec on the 2016 Canyon Stars. Your model, the 3911, is listed with a Gross Vehicle Weight Rating (GVWR) of 26,000 pounds. This is the maximum your coach can weigh, with everything in it (including you). Each axle must also be under its own Gross Axle Wight Rating, also listed. At the moment we'll assume that you haven't loaded your coach so that it's under the GVWR but has an axle (front or rear) over its GAWR.
The Gross Combined Weight Rating (GCWR) of your Canyon Star is 30,000 pounds. This is the maximum allowed weight of the coach plus the weight of the trailer or towed vehicle. Now, 30,000 minus 26,000 means that normally you'd be limited to a towed vehicle that does not exceed 4,000 pounds.
But, if you pack 500 pounds less in the coach, you can tow 500 pounds more. The brochure lists an approximate Net Carrying Capacity (NCC) of 4,582 pounds. So, as "vettenuts" said, if you're careful about what you pack in, you can tow a 4,500 pound vehicle. By the way, "pack in" includes fluids, such as fresh water, gas and waste fluids.
Now, you're in the clear to tow "four down," yes? Not quite.
1) The coach's trailer hitch needs a capacity over that of your towed vehicle weight. Check your owner's manual, or with Newmar.
2) Your vehicle needs to be towable (unless you use a trailer). Honda CRVs model year 2014 and older are usually towable four-down. Check your CRV's owner's manual. It should have a section on towing behind a motorhome.
CRV needs to be towable. As it's likely modified for wheelchair accessibility, you need to review the modifications to ensure that none of them prevent it from being towed. I'd start by reviewing changes to the transmission controls, added electrical components, and ground clearances.
4) If it's not towable four-down, you can see if it's possible to tow it using a dolly or trailer. This will require reviewing many things, including axle loadings, as a trailer exerts downward force on the hitch (and thus the rear axle), that a four-down towbar does not exert. Plus, the trailer or dolly weighs something, and that would subtract from your NCC. Let's hope you don't have to figure this out- that your CRV is towable four-down.
5) Finally, you need to purchase and install the following:
a) a supplemental braking system for the CRV
b) a supplement light system for the CRV
c) a baseplate for the CRV
d) a towbar
e) a cable to connect the coach and CRV
f) safety cables and similar stuff, if not included with the other components
and the optional components
g) a charge line between coach and CRV batteries and/or
h) a new, larger battery in the CRV (if it needs one; some recent model year they increased the size of the battery)
Whew! Not a short summary, I'm afraid.