Welcome to the forum Lauris, you'll find the members on here are a friendly and helpful bunch :) happy new year by the way :)
The a4 b5 is a nice car and there are members on here who use them as daily drivers. Here's some reviews which may help:
Hope they're useful :)
From my personal experience of using an old Audi daily, it can get expensive when things go wrong! But my a6 has done 328k miles and is still doing atleast 2k miles a month. But I love it and wouldn't have it any other way due to the sentimental value of my a6 :)
As I say maintenance is key, so any car your looking at, make sure it has good service history. This is even more important on high mileage examples. When looking at any b5 make sure all electronic items work and the air con works. If the air con is broken it could cost around £1000 to fix if it's the pump or condenser etc.
Also see when the cambelt and water pump we're last changed as these can be around £500 to sort. Don't forget to listen out for any knocking noises when the engine is cold or any white smoke from the exhaust.
Hope I've helped :)
Cheers
Steve