Ticking from engine

[Qmark78]

I have a 99 Mitsubishi Galant low miles 60K

but since i bought it 8k ago it has an intermitent ticking from the engine which does come and go sounds like the tappets or tappet rattling ive put a little extra oil in to no avail

is there any solutions to getting rid of this annoying noise

i dont really want to go to a garage and pay more than the cars worth to have it solved