Need help with deal analysis and advice

[Mark Ito]

Looking at a 4-plex in Dayton, Ohio for $350,000. All units are 2/2s with balconies and larger-than-market av sqft. Average rent in the area is $950 (BP rent estimator). Currently fully leased with long term tenants, totaling $3500/mo gross. Property is in good condition in a low B to high C neighborhood and needs no repairs (but could use cosmetic at the end of lease in order to push rent.) I'm factoring property management (10%), maintenance (10%), vacancy (5%) and capEx (5%) into operating costs ($1050) to give me a NOI of $2450. PITI is looking around $2500 with a 6% 30yr conventional. Am I being too conservative in numbers or anything i'm missing for analyzing a 4-plex? Not conservative enough? I'm hesitant but would love to hear insight from others on how to refine my analysis.