How to investigate the responsibility of the construction unit for the damage of indoor wall paint?

It's simple. As far as you are concerned, you can get compensation. If the construction unit doesn't agree, it can take the following steps: extract the on-site evidence, make a compensation list for offenders, and write a statement in triplicate, one for the mayor, one for the demolition office, one for the residential property, and one for the real estate bureau if there is no property. This is a normal process, and there is no need to communicate with the construction unit. Just wait for the news, and there will be a reply within a week.

If you go to a lawyer alone, you will win the case, but you can't afford the time. And you can satisfy yourself in private and try not to prosecute.

What ordinary people do is to put pressure on the construction unit, which will stimulate contradictions and trigger some other unpleasant and complicated factors. Of course, if you put pressure on the construction party, such as stopping the construction or hindering its construction to the end, it can be solved, but how much compensation you get is the agreed result. It is better to let the construction party take the initiative to find you.

As far as the information you have provided so far, you can only list these methods.