Plumbing, electrical, and roofing I'm fine with.

How about the roof?

Look at mechanical, roofs, appliances etc. to reduce potential for reoccuring repair & maintenance issues and making move-in ready.If you provide a decent analysis of the property which peaks his interest, and he buys and finds you were spot on, whose properties is he gonna look at in the future?

Likewise, you want to have enough cash flow to cover possible capital expenditures like hvac, roofs, etc. that cost more than say repainting a room.Calculate your total out of pocket cost, say for example, 10% down on $80k plus $4k for closing costs, inspections, etc and another $1k per unit repairs.

We are not in a rush to move but would like to start doing repairs and getting estimates for a new roof.

You must expect to have some expenses like, but your analysis does not account anything for that category.I see no mention of reserves; over time, things in the building will need replacement (think heating systems and roof); reserves are important to have so that you can incur the cost to replace those systems down the road without putting yourself into financial stress.

The house is trashed and contractors I've had over there estimate 25-30k in repairs (new roof, new AC in and out) to make it a bare bones rent house, nothing fancy.

If that is the case the offer price goes lower say if a new roof is needed you might deduct 10,000 off the sales price.So from what I am seeing you are at about a 4 to 5 cap without CAPEX.

I even send letters in November reminding my tenants that the best gift they can give is the roof over their family's head.

When a new roof, new siding, new driveway, or new windows are needed, the association will pay for that.