i got a 4x4 trollley jack from halfrauds on sale for 26 quid, fantastic i thought until i tried to slide it under the bottom arms of the mk2 and realised the cars too low! still when you do get it under its mint!
go to a boot sale and look for axle stands and a trolley/bottle jack think there is one in halfords at the mo consists of 2 axle stands and a trolley jack. think its about 40 quid.
at a boot sale you can get either for under a tenner, i bought some ramps for £6.
whatever you do dont get under it while its on a jack or put your hands, feet of any part of your body you value under it without.
make sure if you use a normal scissor jack you use it the correct way and at the correct point on the car.
also check where you are jacking is soild, you never know how its been jacked before!
finally make sure the car is on a level with the handbrake on, i also always leave it in gear.