A differnt way of buying an IP?

A friend's friend knows we're vendor financiers, so he's asked me to see if it would be possible to sell his IP, that's currently leased to the DHA, via an Instalment Sales Contract.  It's something a bit different so I hope it doesn't offend as advertising.

Leased to the DHA until April 2012
Townhouse – 3 bed, 2 bath, double garage
Current rental set at $340 per week (reviewed annually)
Your current variable, interest only, mortgage payment will be $2,463 per month
Located in beautiful Nelson Bay, NSW (Holiday home later?)
For sale via an Installment Sales Contract
Sale price $440,000
$15,000 deposit payable at exchange of contracts
$435,000 payable 7 years from exchange of contracts
Quantity surveyor's, Depreciation Schedule already done.

We have sold a lot of homes via vendor finance but they have always been to owner occupiers.  Selling an IP via vendor finance is something new to us and we'd appreciate your thoughts, i.e. we know owner ocuppiers like the idea, but do investors? Thanks.

Cheers,  Paul