There have been alot of good answers here. To me, the biggest difference is, if there is a home owner's association involved, there are rules you have to obey. If there is no home owner's association, there is little difference in owning a townhome vs any other single family home - other than sharing a wall with your neighbor.
With a home owner's association (HOA), there are by-laws and typically a monthly fee that includes many of the chores a home owner has to do - like shoveling snow, outdoor maintence, etc. Each HOS is a bit different but essentially, you take care of the inside and they'll take care of the outside. Meetings are on a regular basis and if you attend, your ideas can be heard.
With a single family home withoug a HOA, you do the lawn work, shoveling snow, maintain sidewalks, etc.
It all boils down to - how much work do you want to do outside and is it worth it to adhere to the HOA rules so you don't have to worry about it? I'd suggest that if you are interested in a townhome in Blandon, you contact the HOA for a copy of their bylaws (sometimes they have a website) so you can read their rules and what they do for you and then make a decision.
I'd be more than happy to help you do this research if you like. I do handle that area.
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