Would this be a good buy?

[Robert L.]

I am looking to buy this house from another landlord because I see the potential and it's in a great area, but it is also dated inside.  However, it's already rented out by a long-term tenant who doesn't plan to leave.

Purchase Price: $57k
ARV: $105k
Market Rent: $950
Current tenant who has lived there at least 25 years: $700 (I plan to raise her rent like $75/year to get closer to market rent)
Repairs at time of purchase: $0 (because no repairs have been reported since tenant loves her own mess)

If tenant leaves, that's when I need to think about the rehab because:
1) some of the walls have the dated wood kind of look
2) old, dated kitchen cabinets
3) fully carpeted house will need it replaced
4) re-paint inside
5) 150 amps service (should I upgrade?)
6) AC is system is dated 2006
7) Roof probably about 10 years old
8) Plumbing is galvanized pipes

Some will argue that many of these things don't need to be replaced because "if it ain't broke, don't fix it".  Only the paint/carpet would be "needed" for a new tenant move-in along with touching up the kitchen cabinets.  Once it's cleaned up, I should still be able to get $900 for it even though dated-looking.  

What do you think?