Hi I wish you all the best on the future grow my advise I am going to give you is as nice as I could put it even if it didn't sound like it I'm not critising you just give you advice the best I can.
First off I realise you are 70 by what you have said I respect this and know it is hard my advice would be don't rush it put away a little bit every week or month this will mean you will have everything you need for growing.
Second of all please don't scrimp and save on growing equipment well I know it may be expensive doing what I said above will give you enough money for growing goods the reason why I say this is because 15 plants are alot without the equipment needed to control it if they have caught you once growing the same or 5 more your on their radar and I hate to say but you will get caught again if you don't buy the correct equipment I would suggest to save and buy a decent light and a very decent extractor.
All the best hope to see your grow soon