The alternative is a mound system, which you can expect will run 6 figures to install.I have heard stories of parks that make very little money, if any, because the pump truck expenses eats all the profit. 

From estimates received from contractors it might be a maximum budget of $30K to do a garage conversion where I'll rent it out as a 1bd/1ba for about $700 monthly or make it into an AirBnB that can average $2k a month.OR use the 30K to use as a downpayment on a new property with a mortgage but I feel the profits would be less in this market along with the rising interest rates.

And, it's very profitable right now to add value at low cap rates. 

I was more interested in the profits.

@Dan Heuschele was spot on about rent/cost ratios Now, it isn’t the right move for every property (depending on property layout, etc) but the recent change in requirements for adding an ADU (https://www.sandiegocounty.gov/pds/zoning/formfields/PDS-611.pdf) make it a far more feasible/profitable to do so. 

Would be easy to throw on the MLS and sell for profit but the numbers make sense for a long-term rental.Anyone who has purchased a tax foreclosed property - have you had an issue with prior liens after receiving a tax deed?

Especially if I manage to turn a profit on it.

Just a bunch of BS as you know.. they are there to do what we all do and that is snag a good deal.. nothing more nothing less.now in our states on the west coast this is illegal.. and or I should say very strict rules to follow and violation of these is serious.. ergo we no longer do it.. as its not profitable.. just have to let them cycle through the system.

Even in transitional neighborhoods in S.

So the goal is to look for any major (deal killers) that would affect financing or profitability of the property.