I haven’t really kept up with the DIY systems out there other than basic features of what they are capable of for sales comparisons, most if not all of them are wireless only which is fine in a standard 2 or 3 bedroom sub 2k sq ft home, you’ll just want to change batteries every year or so to prevent false alarms that occur more frequently as battery life goes on. All of the pro brands such as Honeywell, DSC and so on can be bought online and installed by the DIYer if you have some electrical and basic programming aptitude. Otherwise most of the basic pro systems are in the general ball park price wise, the basic panels themselves are cheap, the in field devices like motion sensors, glass break detectors and so on add up fast so depending on how many points of protection you want or need will determine the final price.