depends how it's been cared for, if the nite sites are bright, real sig/mecgar mags, how many mags, original box with same s/n as 226, manual.
i buy/sell/trade a lot on backpage/sports equipment for my area.
for the kind on money you're looking to spend, an older triple s/n (frame/barrel/slide) from the mid-nineties, is another option & what i look for, without a rail, unless you need the rail for a light.
this is a link to the current bp listings in my area for sigs.
phoenix sig - sports equipment for sale - backpage.com