I am dealing with this insurance company now.
Not sure if I am allowed to name the company.

Here is the story.
My dad had an accident with this car when he was reversing the car, he sorted of "touched" the front bumper of the other party's car. 
My dad took a photo on the spot.
There is not a scratch of paint or anything. 
But the other party made a claim to their broker, the broker called us, we were like what?

Then 1 month later, they sent us this letter with the wrong vehicles about the other party. 
We were like "ok, investigate and make sure you send us the correct information first."

Then the company came back to us, the vehicle is correct, even if there is no external damage, there could be internal damage.
We said ok, look into it and give me a quote. 
They come back to me with a quote of 300 bucks. 
My dad is ok with settling the case with 300 bucks even we dont think it is our fault.

One month later, which is today, we received another email from the claim officer saying, 

”The total cost of the claim is $998.20. However as you have discussed the issues raised with your parents, and are interested in paying a lump sum amount, I am willing to offer a reduced amount but only if you can pay in the next 10 days.

I will accept $898.50 as full and final settlement of the account.“

I sent an email shortly after receiving this email, asked for a detailed breakdown of the cost.

Here is the question, I agreed to 300 bucks not 900 bucks.

Can they just tripled the quote without even telling me about this?

Any advice would be appreciated. 
Cheers