Repairing a car bumper

[bigegg]

I've got another Lexus, but it's a bit battered.
Basically, the bloke I got it from bought it new in 1998, but he's had his licence taken off him cos he's no longer safe to drive (at 75)
All four corners have been hit - the bumpers need filling and respraying.
What is the best thing to use as filler? Just normal isopon p38? Or is there a better, more flexible, alternative?

 

[Kayos]

I used to use Top Stop Gold, a bit spendy but very flexible

If they are bad then you can get a plastic/fibreglass/filler mix but the name of it escapes me

 

[Cobs]

Tastes in filler are like tastes in women, many and varied! I use U-pol Smooth 7 followed by Top Stop or Top Stop Gold on normal steel bodywork. On bare plastic I'd use a plastic filler like Upol Plast X

Another useful filler to consider having in your toolbox is Upol B which is a waterproof filler, useful for bridging holes or behind wheelarches to prevent further rust.