Congrats on the payment, its nice to get paid for something you love and that will be the key to your tax.
What you can do is register yourself as getting paid for a hobby, this will limit the amount of incorporation you have to do in terms of business bank accounts etc.
The best thing to do is ring your local tax office and ask their advice.
I would definitely check with the landlord and it will all depend on how well you get on with them as to whether they object or not.
It is also down to the interpretation of where you actually conduct your business, as the clause is in the contract to stop you using rented premises as a home office or workshop etc.
I am sure you will be fine as I know lots of self employed people who live in rented flats and they have no problems.
