I noted the age of the roof and 5 years after COE, we replaced it. 

and will be looking for contractors to fix up our home.Can anyone recommend any good contractors for roofing, siding, hardwood floors and plumbing?

The only thing I'll contract out is roofing.  

This one will get a full cosmetic rehab including tearing down interior walls, adding an additional bedroom within the existing living space, re-piping with pex, new roof, HVAC, and exterior stucco.

The roof was so old that most asphalt shingles were down to just the base fiberglass base material.  

I had 2 - 30 yard dumpsters brought in to hall out the plaster and the old roof (which was like 8 layers of shingles).  

Your lender will require this for major expenses like roofing, asphalt, hvac, appliances, etc.Rehab costs would be if the property needs work when you purchase.

HVAC, plumbing, and roofing will most likely be the only things contracted out, yes I know those are major.

I am in Palm Harbor and I use a maintenance company   for ongoing maintenance, and they do roofs, all rehab projects, I have been with them since 2013 when we did a full rehab in Dunedin. 

Real estate has changed my life and my future personal growth has went through the roof.