with the right professionals this could work out well if the existing structure is sound and the price is right.
The QS can tell u 3 things
value of serviced site: you need to adjust if it is on a big site
the spend to-date by major element
the projected spend to finish
keep an eye on the total spend ( ex-site) divided by area to give u a finish cost per sq foot: this number has to be sensible and will help u figure out if purchase price is too high.
For example say the house is 2000 sq feet and say the surveyor tells u that 125 euro per sq foot is the cost to build
so 250,000 is the ex-site build cost.
Then if he tells you that the build cost so far is 100,000 , so 150,000 to finish
If the site is say worth 20,000 then the cost now should be c 120,000 so if they are looking for 200,000 - walk
You will someone at the end to sign off on planning and regulatory compliance
Is it a concrete floor downstairs with all the sewage pipe-work in place.
Does it need a septic tank?