Attorney retainer fee for eviction

[Angela Hollis]

Is $3750 ($250/hr x 15 hours) a reasonable retainer fee  for an eviction of a buyer on a seller financed transaction where buyer is overdue on balloon payment (by 13 months), but continued to pay monthly payments, although most were late and no late fees ever paid in 6 years.  I also just received an email from the buyer this morning stating he is holding out this month's payment and future payments in case he needs them for legal defense. This was a reply to my email stating that after a discussion with an attorney, he advised me to offer an option to close on the house by Feb 1st, 2016 or received his down payment back minus legal fees, cleaning and repairs costs. (I learned this 'cash for keys' just recently on BP) 

To me, it seems a straighforward breach of contract.  Not sure it will require 15 hours, but then again, I've never had to use a lawyer for something like this. 

This is in Texas. (Corpus Christi area)

Any advice would be much appreciated.