It's been on for 7 months? 1.1 is entirely reasonable. I'm not sure what you mean by 'lose credibility'.
If they don't like the offer, what are they going to do? Say no, boo hoo you meanies we deffo won't sell to you.
No, they are going to say, I'm sorry, that offer is too low, can you go any higher?
(I imagine they are holding out for a hotel chain or hospitality company with very deep pockets. That doesn't seem to have happened yet, so you might well be their best bet).
I would be asking you, based on your comments here:
Can you easily afford it? And by easily, I mean, do you have a consistently high level of income and/or capital to be able to repair stuff when it needs doing.
And also: are you really cut out for living somewhere like that?
I only ask, because you seem to think that offering a reduction of 20 percent seems 'scary' and you don't want to 'annoy' the sellers.
Screw your courage to the sticking place, because you are going to have to woman up if you take on a project like this!
(As an aside, those walls are making me itchy).