The mother of the dual Wimbledon champion said she tried to convince him not to purchase Cromlix hotel after going to view it on his behalf.
The tennis coach originally thought the three-time Grand Slam winner wanted to set up home at the property near their home town of Dunblane in Perthshire before he said he would run it as a business.
Murray, 32, bought Cromlix for almost £2 million in 2013 and has since turned it into a five-star hotel with an Albert Roux restaurant that has won a string of hospitality industry awards.
But Mrs Murray, 60, was unimpressed when she visited the premises for a look round.
She said: “The agent who was in charge of selling it came into my brother’s optical practice in Dunblane and gave his card and said ‘Cromlix is about to go on the market, if the family are interested let us know before it goes on the market’.
“I happened to be on the phone to Andy that night and I told him. He said ‘I would quite like to buy that’ and I said ‘What? No you wouldn’t, it’s far too big and it’s falling to bits and nobody lives in houses like that anymore’.
“He went ‘no, no, not to live there, we could run it as a hotel’. I said ‘we don’t know anything about running hotels’ and he said ‘you could find out’. “I came up to have a look at it and really the hotel was falling to bits.
“I completely did my best to put him off. I said ‘it needs far too much work, it’s freezing cold, there’s bats flying around in the library, you definitely don’t want to do this’.
“But he was adamant that he wanted to buy it.
“That started us on a chain of finding a management company that managed these type of country hotels and he decided to go for it.”
During her viewing, Mrs Murray was also stunned to discover the hotel had housed an indoor tennis court on its grounds.
She had struggled to find anywhere to play tennis in the winter and was unaware a covered court was just a few miles from their home.
Speaking on the Walking The Dog podcast, Mrs Murray said: “When I came to look round the grounds this old shed stored farm machinery and they said ‘this used to be the indoor tennis court’.
“I said ‘you are kidding me?’”
Cromlix has become the venue for Murray family gatherings.
The tennis star held his wedding reception at the hotel in April 2015.
The 15 rooms and suites are named after some of Scotland’s most recognisable figures, including Sir Chris Hoy and Annie Lennox.