Cavity Wall Tie replacements in 17th Century property

I have just had a structural survey on an old property which I want to purchase. The surveyor said that it looked like the cavity wall ties would need replacing on the side wall and his reasoning for this was that the wall was leaning out on the left hand side. To look at it was very evident and in the property the floors were uneven. This is a very old property and I can't imagine that it's got a cavity, so I get the impression he was talking about tieing the wall the the main beams. Is this a massive job? Do you have to rip the floors up to do this? Will it cost endless thousands? This is all new to me so I would value anyone's opinions.
Many thanks,

Only a speshul few know about ye olde secrete cavitye ties....

He's probably on about lateral restraint straps, as you surmise. Or it could be a surveyor who hasn't got a clue; they do exist .

It needn't be expensive, there are several proprietary systems (Hilti, HCL etc) on the market, or it is possible to have one's own made up which connect to circular plates on the outside of the wall. The latter cost around £60 each to fabricate, plus another tenner or so if you want bullnose plates (and you will, on an older property); same again to install. Plus VAT. So, if you said £150 a strap all-in, you wouldn't be a million miles away.

If that's actually what he's going on about, then wanging these in at 2m centres along the floor plate should suffice.

Hi Shytalkz,
Thank you for your reply, that sounds exactly what the surveyor was going on about. He did give me the impression that it would cost alot more though because he said that you would need to take up the floorboards to find the beams to attach it to and that may also cause problems with the ceiling below. I've got images of a the house needing to be ripped apart. Was he exagerating or is that necessary? Thanks for the details on the systems available, I will look theses up straight away.
Thanks Again.

HCL options here.

The third and fourth options do not require the floor to be lifted. As a variation on 4, they do one with a sock around the bolt which is filled with a quick-setting resin to expand the sock between the joists.