Then I would also replace old shingles with newer siding, increasing value of the house.At the end of the day I really like the house its on a quiet street next to a country club (the garage was just a bonus for me at the end of the day) and my goal was to lessen my commute.

@Mary JayAny solid non wood structure is better than wood.Survive- Structure still standing, but shingles blown off, windows and doors broken- interior water soaked, clean up costs (make sure part of your insurance).Hurricane clips- look where the roof trusses meet the support beam for the walls. 

These things have a "service life".In this "business" it is wise to have cash reserves to cover large expenses, and avoid losing your renter, and being left with a non-rentable home.What will you do, if the roof shingles blow off in the next storm and the ceiling is leaking buckets of rainwater onto the renters head?

Handyman things are replacing roof shingles, adding a natural gas line to a room for a heater, adding water supply and sewer lines for a new location for 2 washing machines. 

When they own their own home they can establish their own standards.Next thing they will be dictating the type and style of flooring, furnace and roof shingles.

Since taking it over in-house, rents are on time, we have a good maintenance team, and everything is computerized.

If they were things that you couldn't have known about then you can ask and they might.For example I sold a house this summer in as is condition and they came back to me that some roof shingles were missing and the chimney needed some work. 

.#3 Contact Local Contractors for PricingCall local Subcontractors and get budget pricing for common repairs on your typical rehab project.For example, call a roofer and ask what their average cost per Square of Architectural Asphalt Shingle Roofing would be on a 1,500 sf house, with a 6/12 pitch.Note: Some contractors will be reluctant to share pricing without seeing the property, but tell them you are just looking for a rough budget number you can use on future projects.#4 Compile Your Prices into a Spreadsheet or Estimating SoftwareOnce you start to get a better understanding of Labor and Material costs you will want to store this data into a spreadsheet or software that you can use to help you streamline the estimating process.The Book on Estimating Rehab Costs comes with a spreadsheet that you can use to help you populate your own database of labor pricing and material pricing.

Lumber will go up as will shingles, solar panels, electric cars, chicken, tires, pants, dog food.

Based on his description and pictures, the old roof was left as is, but a new set of shingles was set on top.