Ramblin on...and on...and on....
I have a similar problem and have tried to sand but finding some areas are very difficult to sand off old color. Would a wood brightener help at all or is it best to just use a solid stain color to even up the color and try to go a shade lighter?
It is almost impossible to remove solid latex stains as well as any latex color stains. I get pretty good results, but it takes time to remove it and I build it into my price. If the customer wants it off it will cost. If they will not pay the price, then have at it in finding a new customer. Not ever meant to be mean, but time is money and why should the contractor take the hit?
With that said the same contractors do put down inferior products for a cheap price so they can get in and out with a quick $400.
Also, WITH that said. Homeowners should not be trying to search for 10 estimates and pick the lowest price, but choose the best quality from the other contractors. Doing this places a unrealistic goal on the project.
One word to contractors:
Do not suppose because the homeowner who lives in the high end home will shell out the dough to do a job right. More often than not the ones with the lint mixed into their pockets are on a budget, but also save for the projects they perform and thus have the correct idea of what they will have to spend on a quality job.
Note to homeowners:
You are neglecting your home by choosing the cheapest price because it does not take a rocket scientist to figure that after taxes, ins, gas, labor wages and other overhead that a contractor is not going to use Armstrong-Clark oils on your deck or SW Duration/BM Aura when you chop him down on price. You may get a dirty contractor that once used Aura and still has the cut in bucket, but most likely you will get super spec 5 mixed with 1 gallon of water and sprayed on thinly to make his profit margin. In conclusion: Do not cry about the situation YOU forced your contractor into.