I'm interested in buying a 91 accord with a h22a4 swapped into it. The seller says he doesn't have any papers for the engine but claims that it only has just over 100000km. I've done some research and found out that there's no way to know for sure how many km are on it without the papers for the engine. He has also informed me that he didn't do the swap himself it was a "close friend" that had done it and then sold it to him. He's only had it for about a year and says that there's only been 8000km put on it since the swap and he's selling it because he needs the money for school. I am very interested in this car because it is in great condition and also has some mods added to it but I am concerned that there is either more km than he claims or I'm going to have some sort of issues with it down the road. So I'm asking your opinions on if it is worth the risk or not.

Here is the link to the ad if you'd like to check it out.
https://www.facebook.com/marketplace/item/2268041316647591/

 

I myself purchased an H swapped accord. Although mine is a 99. The guy I got it from told me that the only problem with it was a vaccum line which caused a high idle. I'm not a mechanic by any means, so I believed him and bought the car.
Long story short, I have basically had to re-do the entire swap, the mounts were shot, 1 axle was slightly bent, the fuel lines kept bursting, the distributor was almost dead, the back door locks quit working, fans died, blew a top radiator hose.....all in the past few months.
You tube, and thousands in parts and tools. I've learned ALOT working on the accord. My best advice is to really go through the car before you buy it. You don't want to buy someone else's junk like I did.

 

These engine typically hold up pretty well. The critical parts anyways, its all a matter of what is going to go bad, when and how expensive it will be.
If you can get a chance to compression test the engine, I would. Look for 190-220psi on all cylinders, avoid buying the car if the #'s are below 150 on any cylinders or if there are cylinders with great differences.
You can tell alot about a car by the owner and you can tell alot about an engine by the way it sounds and drives.
If you don't mind spending about $800 at a minimum over the course of the next 2-3 years on the car then I would say its worth you buying.