Brian
You have already received a number of responses but I fear some are not as helpful as they should be.......there again, it all depends on an individuals point of view......rather than experience.
The ingredient is INTERVIEW - meet with these people and be professional about it, that IS the only way you will find good staff. It doesn't stop there, maintain contact with them and never forget to praise them for good work!
What I have found here and elsewhere is those employing forget it is not always about money - people will work for you if you're a good employer, offer good job prospects/progression and treat them as a part of the company. You're a young company, don't be afraid of explaining this to any potential cleaner, let them in on YOUR ambitions for your company, you'll be surprised at how many good cleaners will prefer working for you than the one that may pay a slighter higher rate but are real crap to work for - these are the ones that have high turn over of cleaners. It is also important that cleaners receive pay rises, treat cleaners with openess and loyalty and they (majority) will treat you the same.
I would have a problem with all those you've stated that were interested in the position you were offering......
1 - If a person is so reliant on her boyfriend is there a chance she may not turn up for work and worse not even tell you. You need to ask her how she would deal with a situation when her boyfriend can't take her to work. It's only by asking these questions you become more informed and able to make a better judgement.
2 - If someone didn't know what they were applying for then what makes you think this person has a clue on cleaning? It could be that this person, since he didn't care, was making 'up' his applications ready for when he signs on but had no real passion to be a cleaner!
3 - Employing someone that does not speak English is a very risky thing to do - and you are legally entitled to refuse her employment on these grounds since this person would be placed at risk. This person would be placed at risk if she would be a lone worker, what would happen if there was an emergency....how could she communicate to those not understanding Polish? There is also understanding COSHH and health & safety issues - if she were working as part of a team then the risks would be far reduced, however lone working can be a dangerous thing for anyone...............
I agree with Fox - get all those interested to fill out an application form - this will also determine their literacy skills which is extremely important also - if you don't know about their skills then how can you be sure they are getting the correct training?
I'm not sure how you advertised but find alternatives - the benefits office will help out!