roughly how much is rv insurance?

Don't know for you. For us, we pay $1000.00 per year for a 32' 5th wheel, the tow truck and a car. It's all going to depend on what you get, the coverages you need, where you live, your particular circumstances, your credit score, etc.

It is best to figure out what you want, then call your insurance agent and ask him before you buy the RV. Salesman love to tell you their deal is only good for today. don't believe it. Tell them it will be good tomorrow too or you will simply buy it somewhere else.

Then, your best bet would be to call a few insurance companies and get some quotes, right ?

You can also go to their websites and get quotes online.

Because you gave pretty much none of the info that an insurer needs to have, in order to provide a quote to you, no one here can guess what you would pay. Things like your driving history, location of residence, age, driving experience, etc., all come into play to get a quote, and you told us none of those things.

Should be less than your car insurance for similar coverage based on fewer miles driven.