Extending the garage in a "used" house

Hello everyone,

I hope I have found the right section in the forum. I just noticed an interesting house on Immoscout, and a viewing is scheduled in a few days. Due to the market situation here in the area, a quick decision may be necessary in case of an offer, so I wanted to make some preliminary considerations... and ask for your help.

Please imagine a square house with a 3m*6m garage attached on the side. The garage extends halfway beyond the rear (so it protrudes 3m). At the same time, the garage is exactly at the corner of the property. Between the garage and the house, I want to "fill in" and enlarge the garage as a workshop room. I hope you can picture this, sorry for my poor description. Attached is a picture (property (grey), house (blue), garage (green), extension (red)).

Is it possible to tear down/support the garage wall, build a 3m*3m extension with a floor slab and walls, so that a large L-shaped room is created?

Ideally, I want to remove the existing window on the house facing the new extension and install a door there.

The house is refaced with bricks, and the extension should somehow look suitable from the outside.

My questions:
1. Is something like this technically feasible?
2. What range of costs can be expected if one has it done?
3. What portion of the labor costs can be "saved" if earthworks, demolition work according to instructions, electrical work, and assistant tasks are done by myself?

Thank you very much for your help!

Regards,
Dirk

On the one hand, it must be checked whether you are allowed to build on more land. (Bebauungsplan) Then, how much edge development is permitted. 9 meters are already used. Then a structural engineer must calculate to what extent you need a beam. And then you must submit a building application including structural calculations before proceeding with anything. Without approval, it won't work anyway.

Use of the "workshop" at the border must also be checked under building regulations.

Best regards
Dirk Grafe

Then, how much boundary development is allowed. 9 meters are already used.

I believe with us the 9 meters are per property side and in total 15 meters of boundary development are allowed.

Hello everyone,
thank you very much. I think I will abandon the idea and have found another, more practical and cheaper solution.

The garage stays as it is, a double carport can be built at the front part of the house. The back wall of the carport is a house wall. Left side car, right side as a shed. Shed has a door at the front for bicycles. Shed from the outside from the side is in the garden, door for lawn mower and other equipment.

Best regards,
Dirk