Is this a shady rental company?

I'm thinking about renting a house that's kinda old and it's only 670/month but it needs some repairs done like the sink in the bathroom doesn't work and it has stuck windows and doors and the ac/heat don't work as well as there's no hot water. I called the company and asked them could they have this work done before I sign the lease and they told me they can only start fixing it once you sign the lease. My question is what's stopping them from not going through with the repairs or doing a half ass job of it? Is this standard procedure renting out homes?