There could be some reasonable explanations. Sometimes refi's appear as new purchases, but the ownership remains the same. Same thing when a second mortgage is recorded. This would explain the rapid succession of sales and the wide range in pricing.
Regardless, I'm not sure how the history would impact your interest in the home. If it is in great shape, priced and located well and an excellent inspector goes through it with a fine tooth comb so you know what you are getting, move forward.
Check crime stats and history too on the outside chance that the home or area has a past you want to know about that may have affected its previous ownership.
If you are looking at the county records, you may be seeing deeds of trust, refinances, second mortgages or any number of possible recordings against the property.
If you are working with a realtor, they would be the best source of determining the actual history. A foreclosure and sale would be recorded as 2 separate events as well.
I often do a little forensic real estate... (tongue in cheeky joke), to ferret out the real history. What matters most is the current market value, and condition, and check the permit history for work that might have been done, and get a thorough inspection.
PS, I have a great consumer resource site, with Q&A about the home buying processes
If you get stuck, give me a shout!
some of the sites look at any change in financing as a sale might be refinance some forclosures show as a sale also . send me the info i would be happy to find out what is the story as far as being a red flag not as long as you do you due dilligance check everything and do a good inspection you should be fine . email@example.com