Flat Roof Estimate and possibly diy - it myself?

Hello, first timer here, just bought our very first house and the flat roof which covers the garage and kitchen is leaking big time. Chipboard underneath has turned to weetabix about 1.5metes of it at the front, and one of the joists has some mil-dew / damp damage. Around 40sq ft, have had a couple of quotes to re-deck (plywood) and cover with felt for 2800.00 gbp! is that alot? can I get it done cheaper but not comprimise on the standard of finish? I was just lloking at a website aquapanel which is this new rubber membrance that claims it last alot longer then traditional felt? Please help as it keep raining and need to take action...

Cover over the roof with taurpaline for the time being, and get more quotes. If everyone comes back at 2800 then thats the going rate. (Just make sure it isnt the same guy quoting each time pretending to be from different companies! lol)

I find dressing as an old man works well to get a better quote, or as a teenager with long hair and keep looking round as if there are hidden cameras.

don't diy it, you will not be swift enough.
the price sounds a little high, though not totally extortionate.
a well laid three layer felt system with mineral flashings should last a minimum of ten years.

I did a quick google on 'rubber flat roof membrane' and a number of results came up for the supply of an EPDM rubber membrane, with detailed DIY fitting instructions and prices.

I always thought these were specialist fit only, but it seems that they are very easy to fit, and relatively cheap per m2. I know of a few people who have had this type of roof cover for just over 20 years with no problems to date, but it cost them a lot of money at the time

There are also bitumen felt products that don't require a heat torch and are just as long lasting as traditional felt.

Don't use chipboard decking though. Use an external or marine grade ply, and consider insulation if there is none or little there now