Just creating an LLC by filing the document with the state is easy but does not mean that you have asset protection. What matter is the operating agreement. An operating agreement should be tailored for your activity. That is were a good attorney is needed, especially for asset protection.
For asset protection, you don't want to put all your eggs in the same basket as in case of judgement against your real estate property they will now have access to your other income.
LLC can have different tax status. It is very probable that an LLC for an active business won't need the same tax treatment as an LLC for passive investment.
An LLC can also be member or manager managed, single or multi-member. Each has its pro and con depending on your activity.
Last, if you seek anonymity (either to avoid some problems with tenants; or as one of your layer of asset protection), the LLC needs to be opened with that in mind. It is probably not the case for a loan agent.
So yes, it is very likely that you would need another LLC for your activity.
But please consult with an attorney to discuss your specific situation as there may be many other factors you need to take into consideration. Also you need to project yourself in the future to create a structure that will grow with you and won't need to be completely redone every few years down the road.
Most asset protection attorneys offer a free initial phone consultation to discuss your situation and give you a roadmap of what you may need. Make sure that the firm you talk to is also competent in tax optimization as the structure needs to meet both asset protection and tax optimization at the same time.