The materials probably will cost $100 or less if you do it yourself. 

Sometimes they don't include the right materials like wood frame versus brick.

It's not that difficult to work around cabinets plus you save a little on materials.

.$225 is likely only the material cost.

They're metal.

Big companies do not only charge you for their time, they also mark up the cost of materials, and parts.

Unless something material has changed with the condition of the property or the quality of the neighborhood, there is absolutely no reason to lower the rent. 

We're trying to decide on what material to use to replace it.There's not great air flow to inside which is why we're considering moving away from carpet and something that may hold less moisture, easier to clean, look more modern etc.

I always paid for all my materials out of pocket, and then paid the contractor in pre-arranged increments to be paid when certain milestones are hit.

Any of the 3 above and I get concerned about foundation issues or settling and it's the first inspection I have done.I also make general notes of what needs redoing so I can estimate out materials and labor.As I'm going through, I check for plumbing leaks and try light switches.