do I hire a lawyer or appeal property tax alone ?

Hi. I am stuck between trying to file an appeal for my property taxes myself or hiring an attorney to do it for me. Does anyone have any advice in terms of which is more effective. I would normally try to do it myself, however, my property may be a special case. Not only does it have a single family ressidence on the lot, but also a coach house. There are really no houses in the area that fall into that same category (with a coach house attached to it). Will this make it more difficult to prove my case ? Any advice you have to give will be greatly appreciated. Thanks!
I forgot to mention this is a residential property with a total of 3 units in it. 2 are located in the main house (i.e. garden apartment & main apartment), and theres a unit in the coach house as well. I do live on the premisis and have homeowners exemption on the property already.

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