I had a customer that was attending a university part 141 aviation course, he owned a PA-38-112 that he used to commute to parents home in Southern LA on the weekends. The institution sent him a letter advising the the flight time he accumulated in his PA-38 would not be counted towards his 141 requirements - obviously it counted towards his TT and provided an education is aircraft ownership and operations that they could never provide. I suggest verifying with potential institutions what there position would be regarding flight time accumulated in your aircraft.
After graduation there will be the need to accumulate hours and reach the magic 1500, the most common route is flight instruction, may I suggest he look at aerial imagery as well / instead, I'm part owner of an imagery company and our pilots generally acquire 700 - 1000 hours/year flying Cessna 172s or Piper Aztecs around the lower 48, every year we hire 10-15 pilots with wet ink on their commercial certificates.