how do we run CMA’s under the new HAR site?

CMAs have not changed, you can do it in Matrix, contact HAR as they can walk you through it.

I am helping my clients to see their house, and we received a cash offer, the buyer provide his bank statements showing the balance in the account, how can we verify if it is true, do we need authorization from the buyer in order to contact the bank for that?

Verify funds coming from the buyer’s bank account by calling the bank lender even if you are provided contact information for the bank lender, this allows you to verify if the bank institution and the lender are legit.

Hi I'm new in realty business, I wan to have more education about the open houses, sell my self out there

I recommend going to Har.com and checking out their class calendar, and/or check in with your broker, and title companies for more support and development!

how to check the tax record of the property

A few options - from phone app: tap on the 3horizontal lines on the bottom right hand side and scroll down to realist tax search. From the website: log on to your HAR account, on the portal go to the tax tab. Or Hcad.org and do a property search.