Engine question on a possible purchase

[Kitami_EK9]

I've spotted an 98 Integra Type R on my local classifieds. Its got a couple of mods but nothing major. Except seller says cars has low end power issues and hasn't got the funds to fix the problem. My question is, is this most probably a small issue that's easily fixed or is it a costly problem deep within the engines bowels?

any help would be apreciated.

 

[5alldaway]

the most common things to take a look at is the distributer and oxygen sensor