Recovering a flat roof quote

oslamp

Hi

I have a single extension flat roof that needs recoving - 13sq metres.
I got a quote of about £780 + VAT but there are a number of additions that may be needed and I wanted to run this by you.

1. I was told the roof does not have any ventilation and this is not normal and recommend I get this done

2. It looks as though the plywood feels good but if the roof is uncovered and this is chip board it will have to be replaced. Cost - could vary depending on what it looks like but unknown at this stage

3. 3 layers would be put down - bonded material, lead and gravel

4. The company has 'Hotworks' insurance. Is this useful and /or needed?

5. Guarantee for 10 years.

It's the type of job which could bring up unexpected costs and I wanted to get some other opinions on this.

Regards

oslamp