Cost-effective option for carport tool room - tips?

Hi, We are currently having our house built turnkey. Back then, the builder offered us a carport (storage room + 2 covered parking spaces, 2 doors, solid and bricked) for €25,000, which was too expensive for us at the time. An alternative floor plan (side storage room + 1 covered parking space, 1 door, wood) was still supposed to cost €20,000. I understand that the builder would rather use his employees for new builds since his order books are full for 2-3 years (he is really excellent, our house will be finished in 3 weeks and so far we have no complaints). We then decided to build the carport later. A friend who is an architect and has already designed several carports for my family would make us a design. My current plan is that I would like to have the storage room solid and set up the covered parking spaces made of wood myself. Unfortunately, our plot slopes from wide to narrow, so standard solutions are out. That means the width of the carport starts at about 8m wide and narrows to about 6m wide after 6m. Then follows the storage room with about 6m width, which narrows to about 5m width after 3m. I have attached a drawing to explain it better. I have now requested the storage room as a precast concrete garage and received an offer for €18,500 without crane costs. Would anyone have an idea how I can realize the storage room cost-effectively? The planned budget would be between €6,000-8,000.

Would anyone have an idea how I can build the equipment room cost-effectively? The planned budget is between €6000-8000.

Build it yourself. Bought: No way!
Your budget roughly matches what a single prefabricated garage in standard dimensions off the shelf costs, plus the foundation. But you need a custom layout, that won't work with prefabricated parts.

Maybe a wooden frame from the local carpenter.

Your house builder's offer was reasonable, but you probably already know that by now :)

so even made from solid wood (so without clinker/concrete and the like) with simple sheet metal roofing (including condensation protection) you're looking at around €15,000 for such a carport. painting, electrical work, etc... are still missing though.

have you actually finished the floor yet? (paving?) because that will add on top price-wise as well.

Overbuilding pipes (RR) is by the way not the best idea. Better to go around the house once

It is best to go to a carpenter who can build it for you flexibly in timber frame construction. The visual cladding of the carport is a matter of taste - can certainly be done by yourself - or also later to save money.

If a photovoltaic system makes sense on the roof, then I would do that right away... :-)

Building over pipes (RR) is by the way not the best idea. Better to go around the house once

when there is paving on top, it doesn't matter at all. especially if the area is free, with only a roof above.
but you must not concrete or even put a building over the utility lines. the utility providers would have already complained during construction because they also saw the execution drawing with the "carport own work".

with 6-8000€ you can probably manage with the material. but then you have to do everything yourself. can you do that? otherwise better save for another 1-2 years until you have the money. neither make the big compromise now (you'll regret it forever) nor rush it or overestimate your own skills. many wait years with the carport/garage during construction simply because the money is gone. here with us there are some with 3-4 years delay. no problem... we only planted the hedge now after 2.5 years, but had the carport right in the first spring. you just don't have 50,000€ for the outdoor area just lying around...