It is a fairly old example, the same thing has been made in two tone blue since the green livery and in now being produced in blue and white.
They are a classic with strong castings and last a lifetime.
The dust hood is a diy copy. The original metal one is still available from the mfr and will set you back over £160 delivered. I would use that as a negotiating point.
Things to check :
With the machine unplugged, take off the back cover (just a few machine screws) and check the condition of the chain and the sprockets. If they are worn like on an old bike, that has a cost to rectify. I don't know the current cost of 3 sprockets and a chain for Sedgwick but I'd want £100 off. Sprockets wear by getting sharper points and wider U shapes so the chain is less snug on the sprocket.
Unhook the chain from the motor and feel how the motor spindle turns for any sign that the motor bearings need replacing. Put the chain back.
Check the 2 belts for wear but assume you'll need to replace them anyway. They are fairly cheap.
You need to try and assess the big bearings at each end of the cutter block by turning it by hand and again under power. Feel for smoothness when turning by hand and listen when under power. Bearings can be replaced but it's then a fairly major overhaul.
Likewise, examine the in (serrated) and out (smooth) feed rollers. For damage, for being clogged with resin (the infeed needs regular cleaning), and the smooth plain bronze bearings that these run it.
Look at the edge of the infeed table as it leads into the cutter block. Sometimes this gets damaged by a blade coming out of the cutter block. If there's any serious damage it kills the value of the machine. Think down to £200 or £300 max because it would cost a good few hundreds to have it repaired. From the photo this looks pristine so nothing to worry about.
I know what I'm doing so I would take out the blades to check the screws and threads of the wedges that lock the blades in place. These are hex socket screws and though easy enough to replace, you have to be able to get them out. If someone has rounded out a socket tightening a screw, it means drilling and extracting the screw :-(
Try the height adjustment mechanisms to see if they move at all, stiffly or smoothly.
Look at the "stripes" in the upper and lower table castings. They will give you an idea of wear to the tables. These machines are durable so there shouldn't be signs of uneven / concentrated wear. From the photo, the top castings look fine.
If you have a good quality 1 metre steel straightedge, use it to check if the infeed and outfeed tables are parallel or "coplanar". This can be adjusted but it's useful to know whether the machine is right when you're buying it. If not, it suggests the owner doesn't know how to adjust it or doesn't do accurate work with it so is unaware or doesn't care.
A good thing about the machine is the paint looks original and very good for its age. This suggests it hasn't had a cruel life. I would clean this but wouldn't repaint it. Given the age I'd expect the sprockets etc to be worn and need replacing. I'm not impressed with the dust hood.
I'd not normally pay more than £700-800 for an old PT like this but it looks a good example from the photos and with the maintenance jobs done it will be a better machine than any new Chinese one of the size.
See this thread for a full renovation of a larger Sedgwick but of the same vintage.
https://www.ukworkshop.co.uk/threads/sedgwick-mb-planer-thicknesser-full-refurbishment.136008/
The PT255 has only one motor compared to the MB's two so it's a little more complex despite being smaller. Original older motors were grey painted crompton parkinson units and very high quality. If this has been replaced by something else, you want to know why.
If you buy it, download the user manual from the web first and look at the instructions about lifting it. Don't move it by lifting the ends of the tables !!!
HTH.
