@Darren Samson
what kind of loan you can use is a question for a local lender. I have seen loan products that will let you purchase a mixed use property to live in the residential unit, but that is a specific product and you should consult and expert to see the best option for you and your cash on hand.
The biggest reason I would advocate for mixed use is for the reasons you mentioned, the leases are longer, but also the general "issues" around tenants on the residential side don't come into play as much or at all. Also if the property is zoned such that commercial can be there, you've got more options for an eventual redevelopment in my mind. looking longterm who knows what's going to happen in the market.
The largest thing to be cautious about is that with commercial tenants you as the owner often have to put up money in the form of a check or abated or free rent to help the tenant get open for business and build out the space. You'll also likely have longer than tradition residential vacancies.
however, if you could find a loan product that worked for you and your situation, its a fantastic idea in my mind, and worth taking a swing for.