What would you do ? Not the TV show!

bevins wrote: Ask for down payment half up front. Then they pay by hour. So if they don't pay, don't work.

That is the only way i do these jobs, to much time and effort to just have it go to waste.

A last BUT
I think that you are in a smaller market (country) and a not happy customer will easily ruin bussines.
My guts say they do not behave professionall the way the handle their suppliers duties today, so i gues they will never become. Independent what kind of paperwork you do.
Hope Ivm wrong.
Mike

Mike_Eitel wrote: I think that you are in a smaller market (country) and a not happy customer will easily ruin bussines.
My guts say they do not behave professionall the way the handle their suppliers duties today, so i gues they will never become. Independent what kind of paperwork you do.
Hope Ivm wrong.

You are right on all counts, it is a small market of 1.7 Million people, not much professionalism for anything but there are some companies that do professional work for export only, and i hate paperwork so i delegate that part.

I have some experiance in similar job and I must say:
1) customer made big mistake - he bought wrong disassabmled line (without any marks for wiring).
From this point this machine becomes scrap metal.
2) this machine doesn't have project and electrical diagrams - that will help you much, so without it, you can't make anything with that wires.
3) Software is lost - realy, it's not the biggest problem that could be for automation programmer, as me, if first 2 steps are OK (but they are not). BUT if nobody know to the smallest details how that machine should work in steps then, and I'm sure they not, then you can damage something when you will adjust system at the and.
4) Are you work there alone or with somebody? How you are going to find ends on wire alone in big line?

So I think, that this project is dead and it's better not to work on it. But I don't know how it is sophisticated.
What devices does it have and how many of them (asynchronouse motors or servodrives, freaquency drives, etc).
Look at PLC, how many digital inputs/outputs are connected, how many analog inputs/outputs.
If you have a lot of analog outputs/inputs or if you have servodrives, or freaquency drives that are connected to modbus, than this projects is sophisticated and it will be very hard to run it.

But if you have no choise and you must do this job (I hope it's not, and everybody have choice).
As for me, you need to change batteries and use that old PLCs installed, it's not better way but chipest one, and customer will not anderstand your decision to change to new hardware (and realy he will be right).
I must say, that old PLCs are use ugly programmable language similar to assambler. For me, it's very hard language.

If project is not sophisticated (there is some motors that should rotates constantly), then it will be comparatively easy to run it, even if it's big.

So after looking that line one more time, it doesn't matter how is easy or hard it will be for you, you need to convince customer, that it's very hard and high-risk job and to encrease price for this job much.
But if you lose, and customer will not belive that it's hard job, then F**k them off (in mind of course), you will not earn there any good money.

Thank you all for some very good advice, much appreciated.
So far that project is dead as they never bothered to call back. Probably because as i mentioned in the original post one of the guys was convinced it is a 200 to 300 Euro job and i asked for a rough estimate of 3500 to 5000 for labour only.