At the figures you've quoted, I'd sell it now.
We're (just about) four years into a five/six year project, renovating a house we bought as a compromise. Lovely area, interesting old building (detached 400 year old stone mill), but although we were looking for a project - having done several larger ones previously - this one (a repo) didn't excite me on the first viewing. In fact, I hated it - but DH could see the potential and there was nothing else in our budget in the right location. Despite its age, very little character was evident or indeed was buried beneath the surface. Any features the house has are those we've had to add (it's not listed!). We knew it would be a money pit too, but being in a considerably cheaper area (in SW Wales) and the fact we are DIYing much of the work, we're not looking at such steep figures as you OP.
We do have expensive tastes though and like to do stuff well! Also, having moved from the south of England originally we're used to higher costs etc. As a result we've already spent c£100k on the property - adding a borehole, new oil central heating system, rewire, new roof on existing extension, HMKOC kitchen, new bathroom, laundry room, several load-bearing walls removed, relocating kitchen, reconfigured upstairs layout, some garden landscaping...
We still plan to build an extension, convert an outbuilding into a garden room and rebuild the frontage of the existing extension....plus more garden landscaping (we have 0.5 acre which was a barren space four years ago).
We contemplated selling within the first year as I absolutely hated the house (missing our old larger, more characterful house in England terribly), but decided we'd probably lose money. We don't have a mortgage which is one good thing, I s'pose.
Instead we opted to plough on with the work - DH loves it here and hopes I eventually will too. Gradually I'm coming around, although I don't think I'll ever really love it, but it's feeling more like home now - plus a recent valuation indicates the house has doubled in value over the past four years 😀😉