If you have that special rug that's in need of a little TLC, you may want to think twice before immediately going ahead with inexpensive repairs....
It's important to note that repairing a very fine or old oriental rug which is in otherwise good condition should be carefully assessed. Any reputable seller who knows what the rug is will probably be able to tell you right off the bat if your rug is a good candidate for repair.
Generally speaking, newer commercialized rugs and carpets will often be safe to repair without too much assessment. However, pre-WWI rugs and carpets often need much more careful attention if you're looking to preserve or increase value. While low pile and worn out areas may be fixed with expert craftsmanship, what are the possible costs?
For exceptionally rare and unique rugs, it's important to note that originality means a lot to many collectors. There's nothing worse than having a poor repair job, but it doesn't end there.... It's not uncommon for some collectors to be so discriminating they will not go after a rug which has any repairs. The reason for this is due in part to several factors: Technical connoisseurs will always carefully assess repairs not just for quality of workmanship, but also for purity of material. Repairing a rug may mean having to remove original, yet still existing knots, foundation or weft. To some enthusiasts, doing so is not encouraged, even if it means having a carpet with compromised "utility" (although probably would not be in use anyway).
There are others who have the school of thought "if you're going to repair an antique Oriental Rug, you must match it with antique wool, yarn spin, dyes, and ply". While this certainly could be considered the "ideal" situation, one must think about the feasibility of such. There are not too many places which still have bundles of antique wool. Matching a rug knot for knot simply does not make economic sense in other instances. The bottom line, is if you have a very special rug which may have significant value, hold off on repairing it yourself. Take it to a well know, reputable Rug Repair Specialist, and don't be shy about inquiring on the proper repairs in relation to the value of your rug. Assess the cost of repair in relation to the interest of originality and value of the piece as a whole.