The spoiled hedge-fund scion accused of murdering his father for cutting his allowance by $200 might have thought twice if he had known his dad was only worth $585,555.50.

Thomas Gilbert Sr.’s fund, Wainscott Capital Management, never took off and he was in no position to fund the kind of lavish lifestyle of leisure and black-tie parties his son, Thomas Jr., had become used to, according to court papers.

The elder Gilbert — who was allegedly gunned down by his son last year in the allowance spat — had less than $10,000 in stocks and bonds, under $20,000 in cash and retirement accounts, and some $500,000 in “miscellaneous” assets, according to the court papers, which were filed last month in Manhattan Surrogate’s Court by an attorney for Gilbert Sr.’s widow, Shelley Rea Gilbert. Gilbert Sr., 70, also had no life insurance.

The elder Gilbert was once a successful Wall Street money man who lived in an Upper East Side brownstone. But as his bid to start his own hedge fund apparently faltered, he sold the home and started renting a Beekman Place apartment.

Tommy — a Princeton grad with an economics degree who whiled away the days practicing yoga, surfing and hitting the city’s charity circuit — had been feuding with his father over his $400 monthly stipend, police said.

Gilbert Sr., also a Princeton alum, had propped up his 30-year-old kid, including covering his $2,400 rent. The dilettante son constantly complained that “his dad was hypercritical of him, he couldn’t do anything right,” Tommy’s ex-girlfriend, Anna Rothschild, told The Post in an exclusive interview last year.

“He talked a lot about his dad and how mean he was to him and how nothing was good enough,” Rothschild said.

Shelley Rea had thought Gilbert Sr.’s estate was worth at least $1.6 million when she petitioned the court for access to her husband’s funds immediately after his death. She’s paying her son’s legal fees, a source told The Post.

Tommy was a major beneficiary of his father’s will — which was written just two years before the alleged patricide.

Meanwhile, the spoiled son was in court last week griping about the lack of cable TV in his jail cell.

Tommy’s criminal defense lawyer, Alex Spiro, declined to comment. In the past, Spiro has argued that his client is not mentally competent, though an insanity plea was rejected by a judge.

Shelley’s attorney, H. Hedley Stothers Jr., did not return calls seeking comment.