It would seem to me that your business will be seasonal and in Ireland the main season will be June, July & August. Would it not be better to try and run it without a premises until you have traded for a year or work from a web site and exhibition trailer and which can be bought on Ebay for a few grand? (a months rent).
You could pump some of the 20K into marketing and advertising. I suspect that in an Industrial estate you will have very few customers. The business models that are succeeding in the current climate are all about ruducing overhead so you can tread water during lean times. The other alternative is to try and rent space in a school near the coast. You will be located in an urban area, have a ready market, 500- 1000 families and your busy time would be weekends and holidays, when the school is closed. I also don't think you have taken into account the running costs of your premises, rates, ESB, Phones ect and you will have to have somebody there all the time, when maybe you should be out chasing new customers. The premises should be a small part of the overall business plan/vision not the deciding factor. Good luck!!!