I know someone that has a Colt 1911A1 for sale US property, is P marked frame and slide, GHD on frame, 90% cond.  sn 1155*** What would be a fair price.

I bought a really nice one last month with all the right a1 parts on it and at least  95% parkerizing for $800 and was very happy .Mine was made in 1943 and had been remaned at RIA

Need more info, BBL markings, type of hammer, MSH, slide lock, trigger, if anything like the sights have been changed. So much of the worth is in actually being truly correct that it is hard to put an actual figure on it. It could be 1500 to 500 or so depending on originality. The last GI I bought was a 100% Rem Rand [1945] and I paid over a grand for it. A matching number 41 GS inspected [late dec as Sears is assciated with 1942]Colt that had been blued [LONG ago as it was almost gone] but had matching SN frame and slide correct BBL and all parts cost me a bit over 400 bucks. You need to be very careful. Here's some info.

COULD be a 44 frame as production for 43 went to 1155000. So very late 43 or early 44. BBL should be blued and be marked Colt .45 auto. Colt plastic grips with wide rings. Colt stopped marking the SN# under the FPStop around 1,140,000. Some SN# are Duped in 43 but not at your SN#. You still need to check under the FP stop to see if their is a number as there should not be. If all correct and 90% it's worth around a grand +-100 bucks. If not, it depends how bad you want it and if they can be found in your area. Like I said tho do your homework, I do not care if the mag is correct as they can be found pretty easily.