It's nearly always clear from the context what the speaker's role is. There's a slight difference between British and US English. If we want to specify that we're the owner rather than the tenant, we can say "rent out" e.g. "I rent out my flat whilst I'm on holiday". ( I deliberately stuffed that sentence full of so-called Britishisms in order to give it some regional flavour. Flavour..whoops, there I go again) British English also has the verb "let" which has the same meaning, but it tends to be used more in business phrases or notices such as "To Let" than in everyday speech. There is also the verb "hire", which can be used for short-term rental of services, equipment, vehicles or premises. For example, you can hire a room for the day if you need space to hold a meeting. US English may have other ways to get round the problem. It would be interesting to find out what they are.

Yes, the plain verbs are ambiguous and the only way to know the meaning is from context. However, there's a collocation 'rent out' which specifically means to be the owner/landlord (She uses Airbnb to rent out her spare bedroom.) You can also add the prepositions 'to' or 'from' to clarify the context (He rents bicycles to tourists. We're renting a car from Avis.)

Yes, I was going to say that we say „rent out“ when you are the landlord in the US too to distinguish the landlord from the tenant. I tend to favor that construction myself. But, it’s not a strict rule. You can also say „The landlord rents the house to tenants“ the same as you’d say the tenant rents the house from the landlord.“.