Engine Performance problem
1999 Fiat Punto Front Wheel Drive Manual 79,500 miles

hello, i have just got a 1999 t reg punto 1.2 sx. it has 79,500 miles on the clock and a few niggles, i was wondering how much the following repairs should cost me in a garage, or wether going to the scrapper and getting mates to do it would be possible, if the problem isn't large. i have a bolt missing in the Manifold to the downpipe, so im losing some pressure there, and i also have a hole on the bottom of the exhaust, i think its rust, so the whoel thing may need replacing, also the horn isn't beeping and the front left wheel needs a rew rim and tyre as it has been kirbed and the tracking draws to the left. also, the brakes are really damp. how much would all this cost and or what of these could i do myself, except the wheeel which i could do well enough when i get a new one. cheers