Starting to rust - how to look after the bodywork and stone chips?

[VolvoT5]

My car has quite a few stone chips on the bonnet and a few are starting to go rusty (surface rust).  There is also some more significant rust on the driver side door.

Is this normal for the age/mileage (2004/100k) ?  And what is the best way to tackle it and likely cost involved? 

I don't expect the car to be mint at this age but I would like to stop the rust before it is a major issue.  Do I just get a quote from a bodyshop or have a go at a DIY repair or what?

http://imgur.com/W2l6UiA
http://imgur.com/WjPvQCs

[shadrack]

the bonnet one just get a bodyshop, the door one you could diy, however bmw may do it if its rusting on the seam with no reason to rust under the bodywork warrentee

[VolvoT5]

Well I can ask about the 12 year warranty against rust I suppose.  However it appears to be coming from the outside of the door rather than rusting 'inside out', so I suspect they will say it is down to paint work damage.

Anyone know what it costs to get a bonnet sprayed?

[shadrack]

Try 3 or so places for quote, the will vary so much dependant on area etc for forum guessing, also i would use recommendations some spray jobs are shite!  near me i would expect anything from £100-£500 some places advertising at £100 per panel others at 4K for full re spray, im lucky in that i know a retired man (excellent paint jobs) but does it purely as a hobby/ beer money in his double garage thats a make shift booth so i had my e53 almost fully re sprayed for £500,  i would say though now that there wont be too many cheap jobs as just materials to do it are expensive, it cost me £100 in paint, thinners, masking paper etc etc to get the bottom half of my van done with no labour on