装修咋这么贵, 请同学们指点。

位于南加洲, 工业用楼需要装修，有大约5,400SF的办公部分, 两层. 主要装修包括，刷墙, 重铺地毯, 拆除一个房间, 修理喷灌和剪草, 重新普通装修四个单人卫生间. REALTOR推荐了一个CONTRACTOR, 说他信誉好, 收费合理.

可拿到报价,着实下一跳,  同学们帮忙看下, 这个估价离谱吗?
Replace Sod, Trim Landscape, Irrigation repair    7800
Wash windows                                                       1950
Replace damaged ceiling tile                                 1230
New carpet                                                             9900
Painting / includes doors                                       7700
Demo room                                                             540
Replace damaged door                                          275
remove drinking fountain upstair                            210
remodel 4 restrooms                                             10,000 (这是我的估价,当时没想重新装修, 没让他报价)

Supervision                                                            1500
ongoing and final cleanup                                        450

GC Fee  13%                                                         5402
Total                                                                      46,957

REALTOR说推荐他给好几个客户,价格算很合理的. 可还是远远超过我们的预算. 我们对装修没有任何经验, 如果自己做GC, 可行吗?

谢谢.