No matter how much we want to help our friend, I am afraid there will be practical issues for him - not just learning but renting afterwards.
I am a big guy - not ashamed to admit to 5'10 and 17 1/2 stone. This precludes, for example, spinning with an instructor in a PA38 for example, and can also mean max three people in a PA28-140 say with fuel to tabs!
These problems can be solved - with money as has been said (e.g. P28B = no worries for four rugby players a crate of beer and a big load of fuel). The point is to realise that the extra cost is not only going to be during training but also when renting.
Having said all that, if the guy has a goal and the finances it will surely make him feel great to achieve that goal: so save up and go for it!
Andy