AmyL
A good Hotel/apart that Goldtrail do in marmaris is the Keskin. I have stayed there before (although not with Goldtrail) and my sister stayed in june. Its clean, good pool, good location, only a 5 min walk to the beach/bars.
Have you tried looking on teletext holidays? online and on tv, i am pretty sure thats where my sis booked from for the above and she paid £250 for 14 nights.
Good luck getting booked up
loulou