You are relying on here say from the previous owner. Did it really run? Why no keys?
This will be a costly exercise. I bought a VP Calais that I dubbed "Problem Child". So far I have fixed or rectified 46 items. That would have cost a bomb, however most items I have repaired myself.
From what you have said, it doesn't seem you are 'car guy' enough to tackle the issues you have. No disrespect intended.
Here is the 'Zadi Key' slot, you may not have the sticker showing off/on positions
View attachment 259446
If it's on, you will need to access the kick panel area. Remove the panel and behind it there is a steel plate that needs to be unriveted. The rivets are SS and tricky to remove. Behind the plate and on the back of the switch there are 2 pink wires that need to be joined. That will disable the immobilizer in the absense of the key.