Selling my own items I've had years and already made over £1500 now worried about HMRC?

[paulsmename]

With all the hype surrounding the announcement about ebay, vinted air BnB etc....

I took the plunge at the end of december and decided to sell alot of my old Hornby Models, some are in new condition and wanted to make a bit of extra money. To my surprise they seemed really popular so i sold a few more and then so on. already making over £1500 on sales Im starting to get a bit nervous about the whole HMRC issue.  

Now i dont have receipts for these as some were brought for me or i purchased online over the years along with various shops. I read all the time about having to do self assesments as self employed. This is were things get a bit murky i currently work full time for a employer. 

So my questions

how would this work being already working?

Gone over the £1000 allounce will i now be taxed for the £500 or so?

or should I just wait for ebay to decide to pass on information and sit and wait for HMRC to contact me?

because i have a feeling there are many others in the same boat who are not even aware or what this all means as a private seller?

Many thanks

Paul

[pillarboxred]

"Reaching out" is a vogue phrase that has boomed in the last couple of decades: everyone is at it. Where one used to "enquire" or "ask"  one now "reaches out". It has a slightly ingratiating vibe but when HMRC "reaches out" it is like a fisherman with a long sharp stick to land a fat fish.