Contracting out trades to subcontractors

Hello everyone,
has anyone of you had experience with awarding non-warranty relevant trades via specialized internet portals? :confused:
Example:
A home construction company charges 1,500 EUR for painting the fascia board, the company's contracted subcontractor does it for 800 EUR, an offer from a well-known internet portal 500 EUR > execution by a local company > 1,000 EUR saved.
I would therefore like to find out if it would be worthwhile to remove some "turnkey" points from the construction description and outsource some trades.
I would really appreciate your experiences.

Hi,

I know a few cases where the developer went bankrupt in the middle of construction or shortly after completion. Personally, I only want to have the construction company do a little on our house—preferably just the walls and the roof. I want to give the rest to local companies. Therefore, it would already be worthwhile if you can save that much on painting. However, I have to say that I am self-employed, can manage my time well, and the new house is to be built on the same plot of land where I currently live. In addition, I work a lot with craftsmen professionally and have known the companies for years.

Regards Bromi