Can the seller's Realtor stipulate in my counter offer to have me go with a specific mortgage and lender to pay closing cost even though I have been pre-approved and would like to use my own broker and lender?
This question leads me to believe that something is a little strange here.
One thing you want to remember is that you are the buyer and only you will decide what lender you use. If you have a lender already and have a pre-approved mortgage, there is no reason that you cannot use them.
The sellers Realtor is not in a position to tell you where you have to get a mortgage. They may want to be sure your loan allows for certain conditions like paying closing costs etc. which could be the reason for the stipulation.
The FHA home loan is the best product on the market today in my opinion. It allows the greatest flexibility for first time home buyers.
So if the loan product that you have been pre-approved with allows the payment of closing cost, it should not matter to them who you use for the mortgage.
Do not allow yourself to be bullied, you are the customer, without you and your lender there is "NO DEAL" as they say on the TV show!