Not saying title insurance is unimportant, but it is the least important consideration, AS AN UPFRONT CONCERN. Assuming you will need a new mortgage to purchase the home, you will not be able to close the mortgage, and purchase the house, until a satisfactory title search has been performed, and a policy binder issued. Title insurance is typically a cost incurred by the seller, in this case the bank, as it is they that INSURE that you are purchasing the property free of any liens. To be running title searches on properties your looking at, would be a waste of time, and more importantly, your money.
The more important thing is what shape the house is in, and location, basically, does it meet your requirements.....
Purchasing Tax Lien certificates, to gain home ownership, is a long, convoluted process that takes purchasing tax certificates on the subject property for a minimum period of three years, and having to, by law, sell those certificates, at any time that the current owner comes up with the money to buy them back, with interest added. In these cases, due diligence, like title searches, and toxic waste inspections ARE a very real concern.(People generally stop paying taxes for a reason, and NOT always because they're broke

). HTH.