Financing volume 410k € Feasibility assessment

Is it also possible with the architect to agree on individual services and not use entire service phases "as a package"? For example, having the architect carry out the awarding of individual trades and not using the construction supervision/construction management? And agreeing on a price for that?

I am only interested in the basic feasibility; whether it makes sense is another matter ...

I tried the search function, but unfortunately found nothing, and our architect is currently on vacation ...

The building application is approved and the surveyor has been commissioned for the rough staking out.
Amidst all the madness currently happening in the world, at least a little has developed positively for us:

[*]We have been granted a free, adjacent area by the city to store the excavation material, in case it cannot all be stored on the property, and we hope to process everything later on the property to save on landfill costs. All neighbors have used their excavation for filling and terrain modeling, and according to them, it’s optimal to use and compact it for this purpose.
[*]The architect is quite relaxed after we decided not to use the service scopes beyond the building application. If we should still need to tender individual trades, we can simply contact him.
[*]Regarding financing, we just managed to secure 1.55% for 20 years.
[*]In terms of salary, my girlfriend has made significant progress, so we can currently expect a household income of €4,800 (+€300), and from 2023 at first €5,000 (+€500). Now we still have to make sure we get through the construction accident-free and manage the money.