How much to spend on Rental Home Repairs

[Jason McShannock]

We have some rotted floor boards on the front porch of a craftsman style home in Michigan that we have rented for the past four years and in June we are getting new tenants. My question is how would you repair the rotted boards? 
1. Remove the rotted boards, sand entire front porch to remove layers of paint and repaint? Then, it will need to be maintained/painted from time to time in the future. 
2. Remove all flooring boards and replace with plastic decking for a maintenance free repair? 
3. Other ideas? 

The rent is $1,700 per month, 15 year mortgage is $1,500 PITI. The home is a high demand neighborhood near Metro-Detroit and continues to appreciate every year.