This is a very detailed project you are taking on. Houzz doesn't have a lot of plumbing professionals that comment frequently, so you might have more input if you post your question with more details and some photos on a dedicated plumbing forum. I saw a post here at Houzz recently from someone wanting to install just a toilet in the basement and there were so many requirements that it was dizzying. This is probably a project for a professional to evaluate for you unless you are very experienced with plumbing.

I agree. That's such a broad question without any detail that there's not much that we can say other than hire someone who knows what they are doing, is licensed and insured.

I am not a pro but we installed a full bathroom when we finished our basement a couple of years ago. I had originally wanted a powder room (toilet and sink), while my husband wanted the full bath (we installed a tub/shower combo) and the cost of installing the full bathroom was not that much more than the powder room since the ground needed to be broken anyway. (Not that you asked, just putting it out there)

We hired a company that specialized in basement remodels and they had a lot of good ideas, the most important (IMO) was when we were designing the layout to put the bathroom close to where our main sewer pipes were. Those pipes were in the storage area that was going to remain unfinished so we put the bathroom right in front of the storage area, if that makes sense. The ejector pit and shower/tub pipes are in the storage area (actually, the tub is recessed back in that space as well), therefore leaving those things easily accessible if a problem arises.

It might be easier to get answers if you have specific questions, as I cannot think of anything necessarily to "avoid" at this time.

Sorry about my lack of detail. I’m looking for opinions on the following. Sani-Flo up-flush toilet system. Ejector pump system which would require jackhammering up my concrete floor. Or a pumping station in my back yard. I have and old septic tank. We have town sewer which my upstairs bathroom is already tied into and I’m required to tie this basement bathroom to.
Curious what pros and cons people have around these systems. We’re trying to make some improvements before we sell. Thanks again!

Hi Bob, if you plan to sell the home, most non-realtors would advise to save your money as you will rarely get a full return on expensive investments like that which a new buyer may or may not use. I lived in a basement apartment for a year one time, and it's just not a pleasant place to be in most cases. Renting out a basement is also illegal in some jurisdictions being considered a fire escape hazard. Someone using the basement as a gym or for entertainment could easily pop upstairs for the bathroom, and many people appreciate basements for extra storage space. A realtor may ask you to improve the home because it will sell more easily for more money and bring in a larger realtor's commission, but that doesn't at all mean you will recoup more than 60% or so of your investment.

95% of the basement bathrooms here we install using ejector pumps unless the sewer line is coming-in already under the footing and basement floor and the new tie-in is doable.

People who work with lower budgets use UpFlush toilets.