1. The first thing you need to do is to go speak to your town planner in your Municipality to see whether this is feasible, given their spacial development program. For what you want to do, you are going to need their approval, so it makes sense to ask them before you enter the offer on whether, in principle, something like this is possible.
2. Then you need to get a copy of the title deed to see what kind of conditions is contained on it. There could by height restrictions, coverage restrictions, servitudes that will hamper your plans or any host of other factors.
3. You would also need to establish how much the value of the property is going to increase because of your improvements, since this is going to directly impact the rates and taxes that you are going to pay.
4. You also need to establish from your Municipality if they will grant you business rights, whether it is necessary to obtain these rights if you are going to run a boarding house and how long such an application will take.
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